source/wham/src/energy_p_new.F

   1       subroutine etotal(energia,fact)
   2       implicit real*8 (a-h,o-z)
   3       include 'DIMENSIONS'
   4       include 'DIMENSIONS.ZSCOPT'
   5
   6 #ifndef ISNAN
   7       external proc_proc
   8 #endif
   9 #ifdef WINPGI
  10 cMS$ATTRIBUTES C ::  proc_proc
  11 #endif
  12
  13       include 'COMMON.IOUNITS'
  14       double precision energia(0:max_ene),energia1(0:max_ene+1)
  15 #ifdef MPL
  16       include 'COMMON.INFO'
  17       external d_vadd
  18       integer ready
  19 #endif
  20       include 'COMMON.FFIELD'
  21       include 'COMMON.DERIV'
  22       include 'COMMON.INTERACT'
  23       include 'COMMON.SBRIDGE'
  24       include 'COMMON.CHAIN'
  25       double precision fact(6)
  26 cd      write(iout, '(a,i2)')'Calling etotal ipot=',ipot
  27 cd    print *,'nnt=',nnt,' nct=',nct
  28 C
  29 C Compute the side-chain and electrostatic interaction energy
  30 C
  31       goto (101,102,103,104,105) ipot
  32 C Lennard-Jones potential.
  33   101 call elj(evdw,evdw_t)
  34 cd    print '(a)','Exit ELJ'
  35       goto 106
  36 C Lennard-Jones-Kihara potential (shifted).
  37   102 call eljk(evdw,evdw_t)
  38       goto 106
  39 C Berne-Pechukas potential (dilated LJ, angular dependence).
  40   103 call ebp(evdw,evdw_t)
  41       goto 106
  42 C Gay-Berne potential (shifted LJ, angular dependence).
  43   104 call egb(evdw,evdw_t)
  44       goto 106
  45 C Gay-Berne-Vorobjev potential (shifted LJ, angular dependence).
  46   105 call egbv(evdw,evdw_t)
  47 C
  48 C Calculate electrostatic (H-bonding) energy of the main chain.
  49 C
  50   106 call eelec(ees,evdw1,eel_loc,eello_turn3,eello_turn4)
  51 C
  52 C Calculate excluded-volume interaction energy between peptide groups
  53 C and side chains.
  54 C
  55       call escp(evdw2,evdw2_14)
  56 c
  57 c Calculate the bond-stretching energy
  58 c
  59       call ebond(estr)
  60 c      write (iout,*) "estr",estr
  61 C
  62 C Calculate the disulfide-bridge and other energy and the contributions
  63 C from other distance constraints.
  64 cd    print *,'Calling EHPB'
  65       call edis(ehpb)
  66 cd    print *,'EHPB exitted succesfully.'
  67 C
  68 C Calculate the virtual-bond-angle energy.
  69 C
  70       call ebend(ebe)
  71 cd    print *,'Bend energy finished.'
  72 C
  73 C Calculate the SC local energy.
  74 C
  75       call esc(escloc)
  76 cd    print *,'SCLOC energy finished.'
  77 C
  78 C Calculate the virtual-bond torsional energy.
  79 C
  80 cd    print *,'nterm=',nterm
  81       call etor(etors,edihcnstr,fact(1))
  82 C
  83 C 6/23/01 Calculate double-torsional energy
  84 C
  85       call etor_d(etors_d,fact(2))
  86 C
  87 C 21/5/07 Calculate local sicdechain correlation energy
  88 C
  89       call eback_sc_corr(esccor)
  90 C
  91 C 12/1/95 Multi-body terms
  92 C
  93       n_corr=0
  94       n_corr1=0
  95       if (wcorr4.gt.0.0d0 .or. wcorr5.gt.0.0d0 .or. wcorr6.gt.0.0d0
  96      &    .or. wturn6.gt.0.0d0) then
  97 c         print *,"calling multibody_eello"
  98          call multibody_eello(ecorr,ecorr5,ecorr6,eturn6,n_corr,n_corr1)
  99 c         write (*,*) 'n_corr=',n_corr,' n_corr1=',n_corr1
 100 c         print *,ecorr,ecorr5,ecorr6,eturn6
 101       endif
 102       if (wcorr4.eq.0.0d0 .and. wcorr.gt.0.0d0) then
 103          call multibody_hb(ecorr,ecorr5,ecorr6,n_corr,n_corr1)
 104       endif
 105 c      write (iout,*) "ft(6)",fact(6)," evdw",evdw," evdw_t",evdw_t
 106 #ifdef SPLITELE
 107       etot=wsc*(evdw+fact(6)*evdw_t)+wscp*evdw2+welec*fact(1)*ees
 108      & +wvdwpp*evdw1
 109      & +wang*ebe+wtor*fact(1)*etors+wscloc*escloc
 110      & +wstrain*ehpb+wcorr*fact(3)*ecorr+wcorr5*fact(4)*ecorr5
 111      & +wcorr6*fact(5)*ecorr6+wturn4*fact(3)*eello_turn4
 112      & +wturn3*fact(2)*eello_turn3+wturn6*fact(5)*eturn6
 113      & +wel_loc*fact(2)*eel_loc+edihcnstr+wtor_d*fact(2)*etors_d
 114      & +wbond*estr+wsccor*fact(1)*esccor
 115 #else
 116       etot=wsc*(evdw+fact(6)*evdw_t)+wscp*evdw2
 117      & +welec*fact(1)*(ees+evdw1)
 118      & +wang*ebe+wtor*fact(1)*etors+wscloc*escloc
 119      & +wstrain*ehpb+wcorr*fact(3)*ecorr+wcorr5*fact(4)*ecorr5
 120      & +wcorr6*fact(5)*ecorr6+wturn4*fact(3)*eello_turn4
 121      & +wturn3*fact(2)*eello_turn3+wturn6*fact(5)*eturn6
 122      & +wel_loc*fact(2)*eel_loc+edihcnstr+wtor_d*fact(2)*etors_d
 123      & +wbond*estr+wsccor*fact(1)*esccor
 124 #endif
 125       energia(0)=etot
 126       energia(1)=evdw
 127 #ifdef SCP14
 128       energia(2)=evdw2-evdw2_14
 129       energia(17)=evdw2_14
 130 #else
 131       energia(2)=evdw2
 132       energia(17)=0.0d0
 133 #endif
 134 #ifdef SPLITELE
 135       energia(3)=ees
 136       energia(16)=evdw1
 137 #else
 138       energia(3)=ees+evdw1
 139       energia(16)=0.0d0
 140 #endif
 141       energia(4)=ecorr
 142       energia(5)=ecorr5
 143       energia(6)=ecorr6
 144       energia(7)=eel_loc
 145       energia(8)=eello_turn3
 146       energia(9)=eello_turn4
 147       energia(10)=eturn6
 148       energia(11)=ebe
 149       energia(12)=escloc
 150       energia(13)=etors
 151       energia(14)=etors_d
 152       energia(15)=ehpb
 153       energia(18)=estr
 154       energia(19)=esccor
 155       energia(20)=edihcnstr
 156       energia(21)=evdw_t
 157 c      if (dyn_ss) call dyn_set_nss
 158 c detecting NaNQ
 159 #ifdef ISNAN
 160 #ifdef AIX
 161       if (isnan(etot).ne.0) energia(0)=1.0d+99
 162 #else
 163       if (isnan(etot)) energia(0)=1.0d+99
 164 #endif
 165 #else
 166       i=0
 167 #ifdef WINPGI
 168       idumm=proc_proc(etot,i)
 169 #else
 170       call proc_proc(etot,i)
 171 #endif
 172       if(i.eq.1)energia(0)=1.0d+99
 173 #endif
 174 #ifdef MPL
 175 c     endif
 176 #endif
 177       if (calc_grad) then
 178 C
 179 C Sum up the components of the Cartesian gradient.
 180 C
 181 #ifdef SPLITELE
 182       do i=1,nct
 183         do j=1,3
 184           gradc(j,i,icg)=wsc*gvdwc(j,i)+wscp*gvdwc_scp(j,i)+
 185      &                welec*fact(1)*gelc(j,i)+wvdwpp*gvdwpp(j,i)+
 186      &                wbond*gradb(j,i)+
 187      &                wstrain*ghpbc(j,i)+
 188      &                wcorr*fact(3)*gradcorr(j,i)+
 189      &                wel_loc*fact(2)*gel_loc(j,i)+
 190      &                wturn3*fact(2)*gcorr3_turn(j,i)+
 191      &                wturn4*fact(3)*gcorr4_turn(j,i)+
 192      &                wcorr5*fact(4)*gradcorr5(j,i)+
 193      &                wcorr6*fact(5)*gradcorr6(j,i)+
 194      &                wturn6*fact(5)*gcorr6_turn(j,i)+
 195      &                wsccor*fact(2)*gsccorc(j,i)
 196           gradx(j,i,icg)=wsc*gvdwx(j,i)+wscp*gradx_scp(j,i)+
 197      &                  wbond*gradbx(j,i)+
 198      &                  wstrain*ghpbx(j,i)+wcorr*gradxorr(j,i)+
 199      &                  wsccor*fact(2)*gsccorx(j,i)
 200         enddo
 201 #else
 202       do i=1,nct
 203         do j=1,3
 204           gradc(j,i,icg)=wsc*gvdwc(j,i)+wscp*gvdwc_scp(j,i)+
 205      &                welec*fact(1)*gelc(j,i)+wstrain*ghpbc(j,i)+
 206      &                wbond*gradb(j,i)+
 207      &                wcorr*fact(3)*gradcorr(j,i)+
 208      &                wel_loc*fact(2)*gel_loc(j,i)+
 209      &                wturn3*fact(2)*gcorr3_turn(j,i)+
 210      &                wturn4*fact(3)*gcorr4_turn(j,i)+
 211      &                wcorr5*fact(4)*gradcorr5(j,i)+
 212      &                wcorr6*fact(5)*gradcorr6(j,i)+
 213      &                wturn6*fact(5)*gcorr6_turn(j,i)+
 214      &                wsccor*fact(2)*gsccorc(j,i)
 215           gradx(j,i,icg)=wsc*gvdwx(j,i)+wscp*gradx_scp(j,i)+
 216      &                  wbond*gradbx(j,i)+
 217      &                  wstrain*ghpbx(j,i)+wcorr*gradxorr(j,i)+
 218      &                  wsccor*fact(1)*gsccorx(j,i)
 219         enddo
 220 #endif
 221       enddo
 222
 223
 224       do i=1,nres-3
 225         gloc(i,icg)=gloc(i,icg)+wcorr*fact(3)*gcorr_loc(i)
 226      &   +wcorr5*fact(4)*g_corr5_loc(i)
 227      &   +wcorr6*fact(5)*g_corr6_loc(i)
 228      &   +wturn4*fact(3)*gel_loc_turn4(i)
 229      &   +wturn3*fact(2)*gel_loc_turn3(i)
 230      &   +wturn6*fact(5)*gel_loc_turn6(i)
 231      &   +wel_loc*fact(2)*gel_loc_loc(i)
 232      &   +wsccor*fact(1)*gsccor_loc(i)
 233       enddo
 234       endif
 235       return
 236       end
 237 C------------------------------------------------------------------------
 238       subroutine enerprint(energia,fact)
 239       implicit real*8 (a-h,o-z)
 240       include 'DIMENSIONS'
 241       include 'DIMENSIONS.ZSCOPT'
 242       include 'COMMON.IOUNITS'
 243       include 'COMMON.FFIELD'
 244       include 'COMMON.SBRIDGE'
 245       double precision energia(0:max_ene),fact(6)
 246       etot=energia(0)
 247       evdw=energia(1)+fact(6)*energia(21)
 248 #ifdef SCP14
 249       evdw2=energia(2)+energia(17)
 250 #else
 251       evdw2=energia(2)
 252 #endif
 253       ees=energia(3)
 254 #ifdef SPLITELE
 255       evdw1=energia(16)
 256 #endif
 257       ecorr=energia(4)
 258       ecorr5=energia(5)
 259       ecorr6=energia(6)
 260       eel_loc=energia(7)
 261       eello_turn3=energia(8)
 262       eello_turn4=energia(9)
 263       eello_turn6=energia(10)
 264       ebe=energia(11)
 265       escloc=energia(12)
 266       etors=energia(13)
 267       etors_d=energia(14)
 268       ehpb=energia(15)
 269       esccor=energia(19)
 270       edihcnstr=energia(20)
 271       estr=energia(18)
 272 #ifdef SPLITELE
 273       write (iout,10) evdw,wsc,evdw2,wscp,ees,welec*fact(1),evdw1,
 274      &  wvdwpp,
 275      &  estr,wbond,ebe,wang,escloc,wscloc,etors,wtor*fact(1),
 276      &  etors_d,wtor_d*fact(2),ehpb,wstrain,
 277      &  ecorr,wcorr*fact(3),ecorr5,wcorr5*fact(4),ecorr6,wcorr6*fact(5),
 278      &  eel_loc,wel_loc*fact(2),eello_turn3,wturn3*fact(2),
 279      &  eello_turn4,wturn4*fact(3),eello_turn6,wturn6*fact(5),
 280      &  esccor,wsccor*fact(1),edihcnstr,ebr*nss,etot
 281    10 format (/'Virtual-chain energies:'//
 282      & 'EVDW=  ',1pE16.6,' WEIGHT=',1pD16.6,' (SC-SC)'/
 283      & 'EVDW2= ',1pE16.6,' WEIGHT=',1pD16.6,' (SC-p)'/
 284      & 'EES=   ',1pE16.6,' WEIGHT=',1pD16.6,' (p-p elec)'/
 285      & 'EVDWPP=',1pE16.6,' WEIGHT=',1pD16.6,' (p-p VDW)'/
 286      & 'ESTR=  ',1pE16.6,' WEIGHT=',1pD16.6,' (stretching)'/
 287      & 'EBE=   ',1pE16.6,' WEIGHT=',1pD16.6,' (bending)'/
 288      & 'ESC=   ',1pE16.6,' WEIGHT=',1pD16.6,' (SC local)'/
 289      & 'ETORS= ',1pE16.6,' WEIGHT=',1pD16.6,' (torsional)'/
 290      & 'ETORSD=',1pE16.6,' WEIGHT=',1pD16.6,' (double torsional)'/
 291      & 'EHBP=  ',1pE16.6,' WEIGHT=',1pD16.6,
 292      & ' (SS bridges & dist. cnstr.)'/
 293      & 'ECORR4=',1pE16.6,' WEIGHT=',1pD16.6,' (multi-body)'/
 294      & 'ECORR5=',1pE16.6,' WEIGHT=',1pD16.6,' (multi-body)'/
 295      & 'ECORR6=',1pE16.6,' WEIGHT=',1pD16.6,' (multi-body)'/
 296      & 'EELLO= ',1pE16.6,' WEIGHT=',1pD16.6,' (electrostatic-local)'/
 297      & 'ETURN3=',1pE16.6,' WEIGHT=',1pD16.6,' (turns, 3rd order)'/
 298      & 'ETURN4=',1pE16.6,' WEIGHT=',1pD16.6,' (turns, 4th order)'/
 299      & 'ETURN6=',1pE16.6,' WEIGHT=',1pD16.6,' (turns, 6th order)'/
 300      & 'ESCCOR=',1pE16.6,' WEIGHT=',1pD16.6,' (backbone-rotamer corr)'/
 301      & 'EDIHC= ',1pE16.6,' (dihedral angle constraints)'/
 302      & 'ESS=   ',1pE16.6,' (disulfide-bridge intrinsic energy)'/
 303      & 'ETOT=  ',1pE16.6,' (total)')
 304 #else
 305       write (iout,10) evdw,wsc,evdw2,wscp,ees,welec*fact(1),estr,wbond,
 306      &  ebe,wang,escloc,wscloc,etors,wtor*fact(1),etors_d,wtor_d*fact2,
 307      &  ehpb,wstrain,ecorr,wcorr*fact(3),ecorr5,wcorr5*fact(4),
 308      &  ecorr6,wcorr6*fact(5),eel_loc,wel_loc*fact(2),
 309      &  eello_turn3,wturn3*fact(2),eello_turn4,wturn4*fact(3),
 310      &  eello_turn6,wturn6*fact(5),esccor*fact(1),wsccor,
 311      &  edihcnstr,ebr*nss,etot
 312    10 format (/'Virtual-chain energies:'//
 313      & 'EVDW=  ',1pE16.6,' WEIGHT=',1pD16.6,' (SC-SC)'/
 314      & 'EVDW2= ',1pE16.6,' WEIGHT=',1pD16.6,' (SC-p)'/
 315      & 'EES=   ',1pE16.6,' WEIGHT=',1pD16.6,' (p-p)'/
 316      & 'ESTR=  ',1pE16.6,' WEIGHT=',1pD16.6,' (stretching)'/
 317      & 'EBE=   ',1pE16.6,' WEIGHT=',1pD16.6,' (bending)'/
 318      & 'ESC=   ',1pE16.6,' WEIGHT=',1pD16.6,' (SC local)'/
 319      & 'ETORS= ',1pE16.6,' WEIGHT=',1pD16.6,' (torsional)'/
 320      & 'ETORSD=',1pE16.6,' WEIGHT=',1pD16.6,' (double torsional)'/
 321      & 'EHBP=  ',1pE16.6,' WEIGHT=',1pD16.6,
 322      & ' (SS bridges & dist. cnstr.)'/
 323      & 'ECORR4=',1pE16.6,' WEIGHT=',1pD16.6,' (multi-body)'/
 324      & 'ECORR5=',1pE16.6,' WEIGHT=',1pD16.6,' (multi-body)'/
 325      & 'ECORR6=',1pE16.6,' WEIGHT=',1pD16.6,' (multi-body)'/
 326      & 'EELLO= ',1pE16.6,' WEIGHT=',1pD16.6,' (electrostatic-local)'/
 327      & 'ETURN3=',1pE16.6,' WEIGHT=',1pD16.6,' (turns, 3rd order)'/
 328      & 'ETURN4=',1pE16.6,' WEIGHT=',1pD16.6,' (turns, 4th order)'/
 329      & 'ETURN6=',1pE16.6,' WEIGHT=',1pD16.6,' (turns, 6th order)'/
 330      & 'ESCCOR=',1pE16.6,' WEIGHT=',1pD16.6,' (backbone-rotamer corr)'/
 331      & 'EDIHC= ',1pE16.6,' (dihedral angle constraints)'/
 332      & 'ESS=   ',1pE16.6,' (disulfide-bridge intrinsic energy)'/
 333      & 'ETOT=  ',1pE16.6,' (total)')
 334 #endif
 335       return
 336       end
 337 C-----------------------------------------------------------------------
 338       subroutine elj(evdw,evdw_t)
 339 C
 340 C This subroutine calculates the interaction energy of nonbonded side chains
 341 C assuming the LJ potential of interaction.
 342 C
 343       implicit real*8 (a-h,o-z)
 344       include 'DIMENSIONS'
 345       include 'DIMENSIONS.ZSCOPT'
 346       include "DIMENSIONS.COMPAR"
 347       parameter (accur=1.0d-10)
 348       include 'COMMON.GEO'
 349       include 'COMMON.VAR'
 350       include 'COMMON.LOCAL'
 351       include 'COMMON.CHAIN'
 352       include 'COMMON.DERIV'
 353       include 'COMMON.INTERACT'
 354       include 'COMMON.TORSION'
 355       include 'COMMON.ENEPS'
 356       include 'COMMON.SBRIDGE'
 357       include 'COMMON.NAMES'
 358       include 'COMMON.IOUNITS'
 359       include 'COMMON.CONTACTS'
 360       dimension gg(3)
 361       integer icant
 362       external icant
 363 cd    print *,'Entering ELJ nnt=',nnt,' nct=',nct,' expon=',expon
 364       do i=1,210
 365         do j=1,2
 366           eneps_temp(j,i)=0.0d0
 367         enddo
 368       enddo
 369       evdw=0.0D0
 370       evdw_t=0.0d0
 371       do i=iatsc_s,iatsc_e
 372         itypi=itype(i)
 373         itypi1=itype(i+1)
 374         xi=c(1,nres+i)
 375         yi=c(2,nres+i)
 376         zi=c(3,nres+i)
 377 C Change 12/1/95
 378         num_conti=0
 379 C
 380 C Calculate SC interaction energy.
 381 C
 382         do iint=1,nint_gr(i)
 383 cd        write (iout,*) 'i=',i,' iint=',iint,' istart=',istart(i,iint),
 384 cd   &                  'iend=',iend(i,iint)
 385           do j=istart(i,iint),iend(i,iint)
 386             itypj=itype(j)
 387             xj=c(1,nres+j)-xi
 388             yj=c(2,nres+j)-yi
 389             zj=c(3,nres+j)-zi
 390 C Change 12/1/95 to calculate four-body interactions
 391             rij=xj*xj+yj*yj+zj*zj
 392             rrij=1.0D0/rij
 393 c           write (iout,*)'i=',i,' j=',j,' itypi=',itypi,' itypj=',itypj
 394             eps0ij=eps(itypi,itypj)
 395             fac=rrij**expon2
 396             e1=fac*fac*aa(itypi,itypj)
 397             e2=fac*bb(itypi,itypj)
 398             evdwij=e1+e2
 399             ij=icant(itypi,itypj)
 400             eneps_temp(1,ij)=eneps_temp(1,ij)+e1/dabs(eps0ij)
 401             eneps_temp(2,ij)=eneps_temp(2,ij)+e2/eps0ij
 402 cd          sigm=dabs(aa(itypi,itypj)/bb(itypi,itypj))**(1.0D0/6.0D0)
 403 cd          epsi=bb(itypi,itypj)**2/aa(itypi,itypj)
 404 cd          write (iout,'(2(a3,i3,2x),6(1pd12.4)/2(3(1pd12.4),5x)/)')
 405 cd   &        restyp(itypi),i,restyp(itypj),j,aa(itypi,itypj),
 406 cd   &        bb(itypi,itypj),1.0D0/dsqrt(rrij),evdwij,epsi,sigm,
 407 cd   &        (c(k,i),k=1,3),(c(k,j),k=1,3)
 408             if (bb(itypi,itypj).gt.0.0d0) then
 409               evdw=evdw+evdwij
 410             else
 411               evdw_t=evdw_t+evdwij
 412             endif
 413             if (calc_grad) then
 414 C
 415 C Calculate the components of the gradient in DC and X
 416 C
 417             fac=-rrij*(e1+evdwij)
 418             gg(1)=xj*fac
 419             gg(2)=yj*fac
 420             gg(3)=zj*fac
 421             do k=1,3
 422               gvdwx(k,i)=gvdwx(k,i)-gg(k)
 423               gvdwx(k,j)=gvdwx(k,j)+gg(k)
 424             enddo
 425             do k=i,j-1
 426               do l=1,3
 427                 gvdwc(l,k)=gvdwc(l,k)+gg(l)
 428               enddo
 429             enddo
 430             endif
 431 C
 432 C 12/1/95, revised on 5/20/97
 433 C
 434 C Calculate the contact function. The ith column of the array JCONT will
 435 C contain the numbers of atoms that make contacts with the atom I (of numbers
 436 C greater than I). The arrays FACONT and GACONT will contain the values of
 437 C the contact function and its derivative.
 438 C
 439 C Uncomment next line, if the correlation interactions include EVDW explicitly.
 440 c           if (j.gt.i+1 .and. evdwij.le.0.0D0) then
 441 C Uncomment next line, if the correlation interactions are contact function only
 442             if (j.gt.i+1.and. eps0ij.gt.0.0D0) then
 443               rij=dsqrt(rij)
 444               sigij=sigma(itypi,itypj)
 445               r0ij=rs0(itypi,itypj)
 446 C
 447 C Check whether the SC's are not too far to make a contact.
 448 C
 449               rcut=1.5d0*r0ij
 450               call gcont(rij,rcut,1.0d0,0.2d0*rcut,fcont,fprimcont)
 451 C Add a new contact, if the SC's are close enough, but not too close (r<sigma).
 452 C
 453               if (fcont.gt.0.0D0) then
 454 C If the SC-SC distance if close to sigma, apply spline.
 455 cAdam           call gcont(-rij,-1.03d0*sigij,2.0d0*sigij,1.0d0,
 456 cAdam &             fcont1,fprimcont1)
 457 cAdam           fcont1=1.0d0-fcont1
 458 cAdam           if (fcont1.gt.0.0d0) then
 459 cAdam             fprimcont=fprimcont*fcont1+fcont*fprimcont1
 460 cAdam             fcont=fcont*fcont1
 461 cAdam           endif
 462 C Uncomment following 4 lines to have the geometric average of the epsilon0's
 463 cga             eps0ij=1.0d0/dsqrt(eps0ij)
 464 cga             do k=1,3
 465 cga               gg(k)=gg(k)*eps0ij
 466 cga             enddo
 467 cga             eps0ij=-evdwij*eps0ij
 468 C Uncomment for AL's type of SC correlation interactions.
 469 cadam           eps0ij=-evdwij
 470                 num_conti=num_conti+1
 471                 jcont(num_conti,i)=j
 472                 facont(num_conti,i)=fcont*eps0ij
 473                 fprimcont=eps0ij*fprimcont/rij
 474                 fcont=expon*fcont
 475 cAdam           gacont(1,num_conti,i)=-fprimcont*xj+fcont*gg(1)
 476 cAdam           gacont(2,num_conti,i)=-fprimcont*yj+fcont*gg(2)
 477 cAdam           gacont(3,num_conti,i)=-fprimcont*zj+fcont*gg(3)
 478 C Uncomment following 3 lines for Skolnick's type of SC correlation.
 479                 gacont(1,num_conti,i)=-fprimcont*xj
 480                 gacont(2,num_conti,i)=-fprimcont*yj
 481                 gacont(3,num_conti,i)=-fprimcont*zj
 482 cd              write (iout,'(2i5,2f10.5)') i,j,rij,facont(num_conti,i)
 483 cd              write (iout,'(2i3,3f10.5)')
 484 cd   &           i,j,(gacont(kk,num_conti,i),kk=1,3)
 485               endif
 486             endif
 487           enddo      ! j
 488         enddo        ! iint
 489 C Change 12/1/95
 490         num_cont(i)=num_conti
 491       enddo          ! i
 492       if (calc_grad) then
 493       do i=1,nct
 494         do j=1,3
 495           gvdwc(j,i)=expon*gvdwc(j,i)
 496           gvdwx(j,i)=expon*gvdwx(j,i)
 497         enddo
 498       enddo
 499       endif
 500 C******************************************************************************
 501 C
 502 C                              N O T E !!!
 503 C
 504 C To save time, the factor of EXPON has been extracted from ALL components
 505 C of GVDWC and GRADX. Remember to multiply them by this factor before further
 506 C use!
 507 C
 508 C******************************************************************************
 509       return
 510       end
 511 C-----------------------------------------------------------------------------
 512       subroutine eljk(evdw,evdw_t)
 513 C
 514 C This subroutine calculates the interaction energy of nonbonded side chains
 515 C assuming the LJK potential of interaction.
 516 C
 517       implicit real*8 (a-h,o-z)
 518       include 'DIMENSIONS'
 519       include 'DIMENSIONS.ZSCOPT'
 520       include "DIMENSIONS.COMPAR"
 521       include 'COMMON.GEO'
 522       include 'COMMON.VAR'
 523       include 'COMMON.LOCAL'
 524       include 'COMMON.CHAIN'
 525       include 'COMMON.DERIV'
 526       include 'COMMON.INTERACT'
 527       include 'COMMON.ENEPS'
 528       include 'COMMON.IOUNITS'
 529       include 'COMMON.NAMES'
 530       dimension gg(3)
 531       logical scheck
 532       integer icant
 533       external icant
 534 c     print *,'Entering ELJK nnt=',nnt,' nct=',nct,' expon=',expon
 535       do i=1,210
 536         do j=1,2
 537           eneps_temp(j,i)=0.0d0
 538         enddo
 539       enddo
 540       evdw=0.0D0
 541       evdw_t=0.0d0
 542       do i=iatsc_s,iatsc_e
 543         itypi=itype(i)
 544         itypi1=itype(i+1)
 545         xi=c(1,nres+i)
 546         yi=c(2,nres+i)
 547         zi=c(3,nres+i)
 548 C
 549 C Calculate SC interaction energy.
 550 C
 551         do iint=1,nint_gr(i)
 552           do j=istart(i,iint),iend(i,iint)
 553             itypj=itype(j)
 554             xj=c(1,nres+j)-xi
 555             yj=c(2,nres+j)-yi
 556             zj=c(3,nres+j)-zi
 557             rrij=1.0D0/(xj*xj+yj*yj+zj*zj)
 558             fac_augm=rrij**expon
 559             e_augm=augm(itypi,itypj)*fac_augm
 560             r_inv_ij=dsqrt(rrij)
 561             rij=1.0D0/r_inv_ij
 562             r_shift_inv=1.0D0/(rij+r0(itypi,itypj)-sigma(itypi,itypj))
 563             fac=r_shift_inv**expon
 564             e1=fac*fac*aa(itypi,itypj)
 565             e2=fac*bb(itypi,itypj)
 566             evdwij=e_augm+e1+e2
 567             ij=icant(itypi,itypj)
 568             eneps_temp(1,ij)=eneps_temp(1,ij)+(e1+a_augm)
 569      &        /dabs(eps(itypi,itypj))
 570             eneps_temp(2,ij)=eneps_temp(2,ij)+e2/eps(itypi,itypj)
 571 cd          sigm=dabs(aa(itypi,itypj)/bb(itypi,itypj))**(1.0D0/6.0D0)
 572 cd          epsi=bb(itypi,itypj)**2/aa(itypi,itypj)
 573 cd          write (iout,'(2(a3,i3,2x),8(1pd12.4)/2(3(1pd12.4),5x)/)')
 574 cd   &        restyp(itypi),i,restyp(itypj),j,aa(itypi,itypj),
 575 cd   &        bb(itypi,itypj),augm(itypi,itypj),epsi,sigm,
 576 cd   &        sigma(itypi,itypj),1.0D0/dsqrt(rrij),evdwij,
 577 cd   &        (c(k,i),k=1,3),(c(k,j),k=1,3)
 578             if (bb(itypi,itypj).gt.0.0d0) then
 579               evdw=evdw+evdwij
 580             else
 581               evdw_t=evdw_t+evdwij
 582             endif
 583             if (calc_grad) then
 584 C
 585 C Calculate the components of the gradient in DC and X
 586 C
 587             fac=-2.0D0*rrij*e_augm-r_inv_ij*r_shift_inv*(e1+e1+e2)
 588             gg(1)=xj*fac
 589             gg(2)=yj*fac
 590             gg(3)=zj*fac
 591             do k=1,3
 592               gvdwx(k,i)=gvdwx(k,i)-gg(k)
 593               gvdwx(k,j)=gvdwx(k,j)+gg(k)
 594             enddo
 595             do k=i,j-1
 596               do l=1,3
 597                 gvdwc(l,k)=gvdwc(l,k)+gg(l)
 598               enddo
 599             enddo
 600             endif
 601           enddo      ! j
 602         enddo        ! iint
 603       enddo          ! i
 604       if (calc_grad) then
 605       do i=1,nct
 606         do j=1,3
 607           gvdwc(j,i)=expon*gvdwc(j,i)
 608           gvdwx(j,i)=expon*gvdwx(j,i)
 609         enddo
 610       enddo
 611       endif
 612       return
 613       end
 614 C-----------------------------------------------------------------------------
 615       subroutine ebp(evdw,evdw_t)
 616 C
 617 C This subroutine calculates the interaction energy of nonbonded side chains
 618 C assuming the Berne-Pechukas potential of interaction.
 619 C
 620       implicit real*8 (a-h,o-z)
 621       include 'DIMENSIONS'
 622       include 'DIMENSIONS.ZSCOPT'
 623       include "DIMENSIONS.COMPAR"
 624       include 'COMMON.GEO'
 625       include 'COMMON.VAR'
 626       include 'COMMON.LOCAL'
 627       include 'COMMON.CHAIN'
 628       include 'COMMON.DERIV'
 629       include 'COMMON.NAMES'
 630       include 'COMMON.INTERACT'
 631       include 'COMMON.ENEPS'
 632       include 'COMMON.IOUNITS'
 633       include 'COMMON.CALC'
 634       common /srutu/ icall
 635 c     double precision rrsave(maxdim)
 636       logical lprn
 637       integer icant
 638       external icant
 639       do i=1,210
 640         do j=1,2
 641           eneps_temp(j,i)=0.0d0
 642         enddo
 643       enddo
 644       evdw=0.0D0
 645       evdw_t=0.0d0
 646 c     print *,'Entering EBP nnt=',nnt,' nct=',nct,' expon=',expon
 647 c     if (icall.eq.0) then
 648 c       lprn=.true.
 649 c     else
 650         lprn=.false.
 651 c     endif
 652       ind=0
 653       do i=iatsc_s,iatsc_e
 654         itypi=itype(i)
 655         itypi1=itype(i+1)
 656         xi=c(1,nres+i)
 657         yi=c(2,nres+i)
 658         zi=c(3,nres+i)
 659         dxi=dc_norm(1,nres+i)
 660         dyi=dc_norm(2,nres+i)
 661         dzi=dc_norm(3,nres+i)
 662         dsci_inv=vbld_inv(i+nres)
 663 C
 664 C Calculate SC interaction energy.
 665 C
 666         do iint=1,nint_gr(i)
 667           do j=istart(i,iint),iend(i,iint)
 668             ind=ind+1
 669             itypj=itype(j)
 670             dscj_inv=vbld_inv(j+nres)
 671             chi1=chi(itypi,itypj)
 672             chi2=chi(itypj,itypi)
 673             chi12=chi1*chi2
 674             chip1=chip(itypi)
 675             chip2=chip(itypj)
 676             chip12=chip1*chip2
 677             alf1=alp(itypi)
 678             alf2=alp(itypj)
 679             alf12=0.5D0*(alf1+alf2)
 680 C For diagnostics only!!!
 681 c           chi1=0.0D0
 682 c           chi2=0.0D0
 683 c           chi12=0.0D0
 684 c           chip1=0.0D0
 685 c           chip2=0.0D0
 686 c           chip12=0.0D0
 687 c           alf1=0.0D0
 688 c           alf2=0.0D0
 689 c           alf12=0.0D0
 690             xj=c(1,nres+j)-xi
 691             yj=c(2,nres+j)-yi
 692             zj=c(3,nres+j)-zi
 693             dxj=dc_norm(1,nres+j)
 694             dyj=dc_norm(2,nres+j)
 695             dzj=dc_norm(3,nres+j)
 696             rrij=1.0D0/(xj*xj+yj*yj+zj*zj)
 697 cd          if (icall.eq.0) then
 698 cd            rrsave(ind)=rrij
 699 cd          else
 700 cd            rrij=rrsave(ind)
 701 cd          endif
 702             rij=dsqrt(rrij)
 703 C Calculate the angle-dependent terms of energy & contributions to derivatives.
 704             call sc_angular
 705 C Calculate whole angle-dependent part of epsilon and contributions
 706 C to its derivatives
 707             fac=(rrij*sigsq)**expon2
 708             e1=fac*fac*aa(itypi,itypj)
 709             e2=fac*bb(itypi,itypj)
 710             evdwij=eps1*eps2rt*eps3rt*(e1+e2)
 711             eps2der=evdwij*eps3rt
 712             eps3der=evdwij*eps2rt
 713             evdwij=evdwij*eps2rt*eps3rt
 714             ij=icant(itypi,itypj)
 715             aux=eps1*eps2rt**2*eps3rt**2
 716             eneps_temp(1,ij)=eneps_temp(1,ij)+e1*aux
 717      &        /dabs(eps(itypi,itypj))
 718             eneps_temp(2,ij)=eneps_temp(2,ij)+e2*aux/eps(itypi,itypj)
 719             if (bb(itypi,itypj).gt.0.0d0) then
 720               evdw=evdw+evdwij
 721             else
 722               evdw_t=evdw_t+evdwij
 723             endif
 724             if (calc_grad) then
 725             if (lprn) then
 726             sigm=dabs(aa(itypi,itypj)/bb(itypi,itypj))**(1.0D0/6.0D0)
 727             epsi=bb(itypi,itypj)**2/aa(itypi,itypj)
 728 cd            write (iout,'(2(a3,i3,2x),15(0pf7.3))')
 729 cd     &        restyp(itypi),i,restyp(itypj),j,
 730 cd     &        epsi,sigm,chi1,chi2,chip1,chip2,
 731 cd     &        eps1,eps2rt**2,eps3rt**2,1.0D0/dsqrt(sigsq),
 732 cd     &        om1,om2,om12,1.0D0/dsqrt(rrij),
 733 cd     &        evdwij
 734             endif
 735 C Calculate gradient components.
 736             e1=e1*eps1*eps2rt**2*eps3rt**2
 737             fac=-expon*(e1+evdwij)
 738             sigder=fac/sigsq
 739             fac=rrij*fac
 740 C Calculate radial part of the gradient
 741             gg(1)=xj*fac
 742             gg(2)=yj*fac
 743             gg(3)=zj*fac
 744 C Calculate the angular part of the gradient and sum add the contributions
 745 C to the appropriate components of the Cartesian gradient.
 746             call sc_grad
 747             endif
 748           enddo      ! j
 749         enddo        ! iint
 750       enddo          ! i
 751 c     stop
 752       return
 753       end
 754 C-----------------------------------------------------------------------------
 755       subroutine egb(evdw,evdw_t)
 756 C
 757 C This subroutine calculates the interaction energy of nonbonded side chains
 758 C assuming the Gay-Berne potential of interaction.
 759 C
 760       implicit real*8 (a-h,o-z)
 761       include 'DIMENSIONS'
 762       include 'DIMENSIONS.ZSCOPT'
 763       include "DIMENSIONS.COMPAR"
 764       include 'COMMON.GEO'
 765       include 'COMMON.VAR'
 766       include 'COMMON.LOCAL'
 767       include 'COMMON.CHAIN'
 768       include 'COMMON.DERIV'
 769       include 'COMMON.NAMES'
 770       include 'COMMON.INTERACT'
 771       include 'COMMON.ENEPS'
 772       include 'COMMON.IOUNITS'
 773       include 'COMMON.CALC'
 774       include 'COMMON.SBRIDGE'
 775       logical lprn
 776       common /srutu/icall
 777       integer icant
 778       external icant
 779       do i=1,210
 780         do j=1,2
 781           eneps_temp(j,i)=0.0d0
 782         enddo
 783       enddo
 784 c     print *,'Entering EGB nnt=',nnt,' nct=',nct,' expon=',expon
 785       evdw=0.0D0
 786       evdw_t=0.0d0
 787       lprn=.false.
 788 c      if (icall.gt.0) lprn=.true.
 789       ind=0
 790       do i=iatsc_s,iatsc_e
 791         itypi=itype(i)
 792         itypi1=itype(i+1)
 793         xi=c(1,nres+i)
 794         yi=c(2,nres+i)
 795         zi=c(3,nres+i)
 796         dxi=dc_norm(1,nres+i)
 797         dyi=dc_norm(2,nres+i)
 798         dzi=dc_norm(3,nres+i)
 799         dsci_inv=vbld_inv(i+nres)
 800 C
 801 C Calculate SC interaction energy.
 802 C
 803         do iint=1,nint_gr(i)
 804           do j=istart(i,iint),iend(i,iint)
 805 C in case of diagnostics    write (iout,*) "TU SZUKAJ",i,j,dyn_ss_mask(i),dyn_ss_mask(j)
 806 C /06/28/2013 Adasko: In case of dyn_ss - dynamic disulfide bond
 807 C formation no electrostatic interactions should be calculated. If it
 808 C would be allowed NaN would appear
 809             IF (dyn_ss_mask(i).and.dyn_ss_mask(j)) THEN
 810 C /06/28/2013 Adasko: dyn_ss_mask is logical statement wheather this Cys
 811 C residue can or cannot form disulfide bond. There is still bug allowing
 812 C Cys...Cys...Cys bond formation
 813               call dyn_ssbond_ene(i,j,evdwij)
 814 C /06/28/2013 Adasko: dyn_ssbond_ene is dynamic SS bond foration energy
 815 C function in ssMD.F
 816               evdw=evdw+evdwij
 817 c              if (energy_dec) write (iout,'(a6,2i5,0pf7.3,a3)')
 818 c     &                        'evdw',i,j,evdwij,' ss'
 819             ELSE
 820             ind=ind+1
 821             itypj=itype(j)
 822             dscj_inv=vbld_inv(j+nres)
 823             sig0ij=sigma(itypi,itypj)
 824             chi1=chi(itypi,itypj)
 825             chi2=chi(itypj,itypi)
 826             chi12=chi1*chi2
 827             chip1=chip(itypi)
 828             chip2=chip(itypj)
 829             chip12=chip1*chip2
 830             alf1=alp(itypi)
 831             alf2=alp(itypj)
 832             alf12=0.5D0*(alf1+alf2)
 833 C For diagnostics only!!!
 834 c           chi1=0.0D0
 835 c           chi2=0.0D0
 836 c           chi12=0.0D0
 837 c           chip1=0.0D0
 838 c           chip2=0.0D0
 839 c           chip12=0.0D0
 840 c           alf1=0.0D0
 841 c           alf2=0.0D0
 842 c           alf12=0.0D0
 843             xj=c(1,nres+j)-xi
 844             yj=c(2,nres+j)-yi
 845             zj=c(3,nres+j)-zi
 846             dxj=dc_norm(1,nres+j)
 847             dyj=dc_norm(2,nres+j)
 848             dzj=dc_norm(3,nres+j)
 849 c            write (iout,*) i,j,xj,yj,zj
 850             rrij=1.0D0/(xj*xj+yj*yj+zj*zj)
 851             rij=dsqrt(rrij)
 852 C Calculate angle-dependent terms of energy and contributions to their
 853 C derivatives.
 854             call sc_angular
 855             sigsq=1.0D0/sigsq
 856             sig=sig0ij*dsqrt(sigsq)
 857             rij_shift=1.0D0/rij-sig+sig0ij
 858 C I hate to put IF's in the loops, but here don't have another choice!!!!
 859             if (rij_shift.le.0.0D0) then
 860               evdw=1.0D20
 861               return
 862             endif
 863             sigder=-sig*sigsq
 864 c---------------------------------------------------------------
 865             rij_shift=1.0D0/rij_shift
 866             fac=rij_shift**expon
 867             e1=fac*fac*aa(itypi,itypj)
 868             e2=fac*bb(itypi,itypj)
 869             evdwij=eps1*eps2rt*eps3rt*(e1+e2)
 870             eps2der=evdwij*eps3rt
 871             eps3der=evdwij*eps2rt
 872             evdwij=evdwij*eps2rt*eps3rt
 873             if (bb(itypi,itypj).gt.0) then
 874               evdw=evdw+evdwij
 875             else
 876               evdw_t=evdw_t+evdwij
 877             endif
 878             ij=icant(itypi,itypj)
 879             aux=eps1*eps2rt**2*eps3rt**2
 880             eneps_temp(1,ij)=eneps_temp(1,ij)+aux*e1
 881      &        /dabs(eps(itypi,itypj))
 882             eneps_temp(2,ij)=eneps_temp(2,ij)+aux*e2/eps(itypi,itypj)
 883 c            write (iout,*) "i",i," j",j," itypi",itypi," itypj",itypj,
 884 c     &         " ij",ij," eneps",aux*e1/dabs(eps(itypi,itypj)),
 885 c     &         aux*e2/eps(itypi,itypj)
 886 c       write (iout,'(a6,2i5,0pf7.3)') 'evdw',i,j,evdwij
 887             if (lprn) then
 888             sigm=dabs(aa(itypi,itypj)/bb(itypi,itypj))**(1.0D0/6.0D0)
 889             epsi=bb(itypi,itypj)**2/aa(itypi,itypj)
 890             write (iout,'(2(a3,i3,2x),17(0pf7.3))')
 891      &        restyp(itypi),i,restyp(itypj),j,
 892      &        epsi,sigm,chi1,chi2,chip1,chip2,
 893      &        eps1,eps2rt**2,eps3rt**2,sig,sig0ij,
 894      &        om1,om2,om12,1.0D0/rij,1.0D0/rij_shift,
 895      &        evdwij
 896             endif
 897             if (calc_grad) then
 898 C Calculate gradient components.
 899             e1=e1*eps1*eps2rt**2*eps3rt**2
 900             fac=-expon*(e1+evdwij)*rij_shift
 901             sigder=fac*sigder
 902             fac=rij*fac
 903 C Calculate the radial part of the gradient
 904             gg(1)=xj*fac
 905             gg(2)=yj*fac
 906             gg(3)=zj*fac
 907 C Calculate angular part of the gradient.
 908             call sc_grad
 909             endif
 910             ENDIF    ! dyn_ss
 911           enddo      ! j
 912         enddo        ! iint
 913       enddo          ! i
 914       return
 915       end
 916 C-----------------------------------------------------------------------------
 917       subroutine egbv(evdw,evdw_t)
 918 C
 919 C This subroutine calculates the interaction energy of nonbonded side chains
 920 C assuming the Gay-Berne-Vorobjev potential of interaction.
 921 C
 922       implicit real*8 (a-h,o-z)
 923       include 'DIMENSIONS'
 924       include 'DIMENSIONS.ZSCOPT'
 925       include "DIMENSIONS.COMPAR"
 926       include 'COMMON.GEO'
 927       include 'COMMON.VAR'
 928       include 'COMMON.LOCAL'
 929       include 'COMMON.CHAIN'
 930       include 'COMMON.DERIV'
 931       include 'COMMON.NAMES'
 932       include 'COMMON.INTERACT'
 933       include 'COMMON.ENEPS'
 934       include 'COMMON.IOUNITS'
 935       include 'COMMON.CALC'
 936       common /srutu/ icall
 937       logical lprn
 938       integer icant
 939       external icant
 940       do i=1,210
 941         do j=1,2
 942           eneps_temp(j,i)=0.0d0
 943         enddo
 944       enddo
 945       evdw=0.0D0
 946       evdw_t=0.0d0
 947 c     print *,'Entering EGB nnt=',nnt,' nct=',nct,' expon=',expon
 948       evdw=0.0D0
 949       lprn=.false.
 950 c      if (icall.gt.0) lprn=.true.
 951       ind=0
 952       do i=iatsc_s,iatsc_e
 953         itypi=itype(i)
 954         itypi1=itype(i+1)
 955         xi=c(1,nres+i)
 956         yi=c(2,nres+i)
 957         zi=c(3,nres+i)
 958         dxi=dc_norm(1,nres+i)
 959         dyi=dc_norm(2,nres+i)
 960         dzi=dc_norm(3,nres+i)
 961         dsci_inv=vbld_inv(i+nres)
 962 C
 963 C Calculate SC interaction energy.
 964 C
 965         do iint=1,nint_gr(i)
 966           do j=istart(i,iint),iend(i,iint)
 967             ind=ind+1
 968             itypj=itype(j)
 969             dscj_inv=vbld_inv(j+nres)
 970             sig0ij=sigma(itypi,itypj)
 971             r0ij=r0(itypi,itypj)
 972             chi1=chi(itypi,itypj)
 973             chi2=chi(itypj,itypi)
 974             chi12=chi1*chi2
 975             chip1=chip(itypi)
 976             chip2=chip(itypj)
 977             chip12=chip1*chip2
 978             alf1=alp(itypi)
 979             alf2=alp(itypj)
 980             alf12=0.5D0*(alf1+alf2)
 981 C For diagnostics only!!!
 982 c           chi1=0.0D0
 983 c           chi2=0.0D0
 984 c           chi12=0.0D0
 985 c           chip1=0.0D0
 986 c           chip2=0.0D0
 987 c           chip12=0.0D0
 988 c           alf1=0.0D0
 989 c           alf2=0.0D0
 990 c           alf12=0.0D0
 991             xj=c(1,nres+j)-xi
 992             yj=c(2,nres+j)-yi
 993             zj=c(3,nres+j)-zi
 994             dxj=dc_norm(1,nres+j)
 995             dyj=dc_norm(2,nres+j)
 996             dzj=dc_norm(3,nres+j)
 997             rrij=1.0D0/(xj*xj+yj*yj+zj*zj)
 998             rij=dsqrt(rrij)
 999 C Calculate angle-dependent terms of energy and contributions to their
1000 C derivatives.
1001             call sc_angular
1002             sigsq=1.0D0/sigsq
1003             sig=sig0ij*dsqrt(sigsq)
1004             rij_shift=1.0D0/rij-sig+r0ij
1005 C I hate to put IF's in the loops, but here don't have another choice!!!!
1006             if (rij_shift.le.0.0D0) then
1007               evdw=1.0D20
1008               return
1009             endif
1010             sigder=-sig*sigsq
1011 c---------------------------------------------------------------
1012             rij_shift=1.0D0/rij_shift
1013             fac=rij_shift**expon
1014             e1=fac*fac*aa(itypi,itypj)
1015             e2=fac*bb(itypi,itypj)
1016             evdwij=eps1*eps2rt*eps3rt*(e1+e2)
1017             eps2der=evdwij*eps3rt
1018             eps3der=evdwij*eps2rt
1019             fac_augm=rrij**expon
1020             e_augm=augm(itypi,itypj)*fac_augm
1021             evdwij=evdwij*eps2rt*eps3rt
1022             if (bb(itypi,itypj).gt.0.0d0) then
1023               evdw=evdw+evdwij+e_augm
1024             else
1025               evdw_t=evdw_t+evdwij+e_augm
1026             endif
1027             ij=icant(itypi,itypj)
1028             aux=eps1*eps2rt**2*eps3rt**2
1029             eneps_temp(1,ij)=eneps_temp(1,ij)+aux*(e1+e_augm)
1030      &        /dabs(eps(itypi,itypj))
1031             eneps_temp(2,ij)=eneps_temp(2,ij)+aux*e2/eps(itypi,itypj)
1032 c            eneps_temp(ij)=eneps_temp(ij)
1033 c     &         +(evdwij+e_augm)/eps(itypi,itypj)
1034 c            if (lprn) then
1035 c            sigm=dabs(aa(itypi,itypj)/bb(itypi,itypj))**(1.0D0/6.0D0)
1036 c            epsi=bb(itypi,itypj)**2/aa(itypi,itypj)
1037 c            write (iout,'(2(a3,i3,2x),17(0pf7.3))')
1038 c     &        restyp(itypi),i,restyp(itypj),j,
1039 c     &        epsi,sigm,sig,(augm(itypi,itypj)/epsi)**(1.0D0/12.0D0),
1040 c     &        chi1,chi2,chip1,chip2,
1041 c     &        eps1,eps2rt**2,eps3rt**2,
1042 c     &        om1,om2,om12,1.0D0/rij,1.0D0/rij_shift,
1043 c     &        evdwij+e_augm
1044 c            endif
1045             if (calc_grad) then
1046 C Calculate gradient components.
1047             e1=e1*eps1*eps2rt**2*eps3rt**2
1048             fac=-expon*(e1+evdwij)*rij_shift
1049             sigder=fac*sigder
1050             fac=rij*fac-2*expon*rrij*e_augm
1051 C Calculate the radial part of the gradient
1052             gg(1)=xj*fac
1053             gg(2)=yj*fac
1054             gg(3)=zj*fac
1055 C Calculate angular part of the gradient.
1056             call sc_grad
1057             endif
1058           enddo      ! j
1059         enddo        ! iint
1060       enddo          ! i
1061       return
1062       end
1063 C-----------------------------------------------------------------------------
1064       subroutine sc_angular
1065 C Calculate eps1,eps2,eps3,sigma, and parts of their derivatives in om1,om2,
1066 C om12. Called by ebp, egb, and egbv.
1067       implicit none
1068       include 'COMMON.CALC'
1069       erij(1)=xj*rij
1070       erij(2)=yj*rij
1071       erij(3)=zj*rij
1072       om1=dxi*erij(1)+dyi*erij(2)+dzi*erij(3)
1073       om2=dxj*erij(1)+dyj*erij(2)+dzj*erij(3)
1074       om12=dxi*dxj+dyi*dyj+dzi*dzj
1075       chiom12=chi12*om12
1076 C Calculate eps1(om12) and its derivative in om12
1077       faceps1=1.0D0-om12*chiom12
1078       faceps1_inv=1.0D0/faceps1
1079       eps1=dsqrt(faceps1_inv)
1080 C Following variable is eps1*deps1/dom12
1081       eps1_om12=faceps1_inv*chiom12
1082 C Calculate sigma(om1,om2,om12) and the derivatives of sigma**2 in om1,om2,
1083 C and om12.
1084       om1om2=om1*om2
1085       chiom1=chi1*om1
1086       chiom2=chi2*om2
1087       facsig=om1*chiom1+om2*chiom2-2.0D0*om1om2*chiom12
1088       sigsq=1.0D0-facsig*faceps1_inv
1089       sigsq_om1=(chiom1-chiom12*om2)*faceps1_inv
1090       sigsq_om2=(chiom2-chiom12*om1)*faceps1_inv
1091       sigsq_om12=-chi12*(om1om2*faceps1-om12*facsig)*faceps1_inv**2
1092 C Calculate eps2 and its derivatives in om1, om2, and om12.
1093       chipom1=chip1*om1
1094       chipom2=chip2*om2
1095       chipom12=chip12*om12
1096       facp=1.0D0-om12*chipom12
1097       facp_inv=1.0D0/facp
1098       facp1=om1*chipom1+om2*chipom2-2.0D0*om1om2*chipom12
1099 C Following variable is the square root of eps2
1100       eps2rt=1.0D0-facp1*facp_inv
1101 C Following three variables are the derivatives of the square root of eps
1102 C in om1, om2, and om12.
1103       eps2rt_om1=-4.0D0*(chipom1-chipom12*om2)*facp_inv
1104       eps2rt_om2=-4.0D0*(chipom2-chipom12*om1)*facp_inv
1105       eps2rt_om12=4.0D0*chip12*(om1om2*facp-om12*facp1)*facp_inv**2
1106 C Evaluate the "asymmetric" factor in the VDW constant, eps3
1107       eps3rt=1.0D0-alf1*om1+alf2*om2-alf12*om12
1108 C Calculate whole angle-dependent part of epsilon and contributions
1109 C to its derivatives
1110       return
1111       end
1112 C----------------------------------------------------------------------------
1113       subroutine sc_grad
1114       implicit real*8 (a-h,o-z)
1115       include 'DIMENSIONS'
1116       include 'DIMENSIONS.ZSCOPT'
1117       include 'COMMON.CHAIN'
1118       include 'COMMON.DERIV'
1119       include 'COMMON.CALC'
1120       double precision dcosom1(3),dcosom2(3)
1121       eom1=eps2der*eps2rt_om1-2.0D0*alf1*eps3der+sigder*sigsq_om1
1122       eom2=eps2der*eps2rt_om2+2.0D0*alf2*eps3der+sigder*sigsq_om2
1123       eom12=evdwij*eps1_om12+eps2der*eps2rt_om12
1124      &     -2.0D0*alf12*eps3der+sigder*sigsq_om12
1125       do k=1,3
1126         dcosom1(k)=rij*(dc_norm(k,nres+i)-om1*erij(k))
1127         dcosom2(k)=rij*(dc_norm(k,nres+j)-om2*erij(k))
1128       enddo
1129       do k=1,3
1130         gg(k)=gg(k)+eom1*dcosom1(k)+eom2*dcosom2(k)
1131       enddo
1132       do k=1,3
1133         gvdwx(k,i)=gvdwx(k,i)-gg(k)
1134      &            +(eom12*(dc_norm(k,nres+j)-om12*dc_norm(k,nres+i))
1135      &            +eom1*(erij(k)-om1*dc_norm(k,nres+i)))*dsci_inv
1136         gvdwx(k,j)=gvdwx(k,j)+gg(k)
1137      &            +(eom12*(dc_norm(k,nres+i)-om12*dc_norm(k,nres+j))
1138      &            +eom2*(erij(k)-om2*dc_norm(k,nres+j)))*dscj_inv
1139       enddo
1140 C
1141 C Calculate the components of the gradient in DC and X
1142 C
1143       do k=i,j-1
1144         do l=1,3
1145           gvdwc(l,k)=gvdwc(l,k)+gg(l)
1146         enddo
1147       enddo
1148       return
1149       end
1150 c------------------------------------------------------------------------------
1151       subroutine vec_and_deriv
1152       implicit real*8 (a-h,o-z)
1153       include 'DIMENSIONS'
1154       include 'DIMENSIONS.ZSCOPT'
1155       include 'COMMON.IOUNITS'
1156       include 'COMMON.GEO'
1157       include 'COMMON.VAR'
1158       include 'COMMON.LOCAL'
1159       include 'COMMON.CHAIN'
1160       include 'COMMON.VECTORS'
1161       include 'COMMON.DERIV'
1162       include 'COMMON.INTERACT'
1163       dimension uyder(3,3,2),uzder(3,3,2),vbld_inv_temp(2)
1164 C Compute the local reference systems. For reference system (i), the
1165 C X-axis points from CA(i) to CA(i+1), the Y axis is in the
1166 C CA(i)-CA(i+1)-CA(i+2) plane, and the Z axis is perpendicular to this plane.
1167       do i=1,nres-1
1168 c          if (i.eq.nres-1 .or. itel(i+1).eq.0) then
1169           if (i.eq.nres-1) then
1170 C Case of the last full residue
1171 C Compute the Z-axis
1172             call vecpr(dc_norm(1,i),dc_norm(1,i-1),uz(1,i))
1173             costh=dcos(pi-theta(nres))
1174             fac=1.0d0/dsqrt(1.0d0-costh*costh)
1175             do k=1,3
1176               uz(k,i)=fac*uz(k,i)
1177             enddo
1178             if (calc_grad) then
1179 C Compute the derivatives of uz
1180             uzder(1,1,1)= 0.0d0
1181             uzder(2,1,1)=-dc_norm(3,i-1)
1182             uzder(3,1,1)= dc_norm(2,i-1)
1183             uzder(1,2,1)= dc_norm(3,i-1)
1184             uzder(2,2,1)= 0.0d0
1185             uzder(3,2,1)=-dc_norm(1,i-1)
1186             uzder(1,3,1)=-dc_norm(2,i-1)
1187             uzder(2,3,1)= dc_norm(1,i-1)
1188             uzder(3,3,1)= 0.0d0
1189             uzder(1,1,2)= 0.0d0
1190             uzder(2,1,2)= dc_norm(3,i)
1191             uzder(3,1,2)=-dc_norm(2,i)
1192             uzder(1,2,2)=-dc_norm(3,i)
1193             uzder(2,2,2)= 0.0d0
1194             uzder(3,2,2)= dc_norm(1,i)
1195             uzder(1,3,2)= dc_norm(2,i)
1196             uzder(2,3,2)=-dc_norm(1,i)
1197             uzder(3,3,2)= 0.0d0
1198             endif
1199 C Compute the Y-axis
1200             facy=fac
1201             do k=1,3
1202               uy(k,i)=fac*(dc_norm(k,i-1)-costh*dc_norm(k,i))
1203             enddo
1204             if (calc_grad) then
1205 C Compute the derivatives of uy
1206             do j=1,3
1207               do k=1,3
1208                 uyder(k,j,1)=2*dc_norm(k,i-1)*dc_norm(j,i)
1209      &                        -dc_norm(k,i)*dc_norm(j,i-1)
1210                 uyder(k,j,2)=-dc_norm(j,i)*dc_norm(k,i)
1211               enddo
1212               uyder(j,j,1)=uyder(j,j,1)-costh
1213               uyder(j,j,2)=1.0d0+uyder(j,j,2)
1214             enddo
1215             do j=1,2
1216               do k=1,3
1217                 do l=1,3
1218                   uygrad(l,k,j,i)=uyder(l,k,j)
1219                   uzgrad(l,k,j,i)=uzder(l,k,j)
1220                 enddo
1221               enddo
1222             enddo
1223             call unormderiv(uy(1,i),uyder(1,1,1),facy,uygrad(1,1,1,i))
1224             call unormderiv(uy(1,i),uyder(1,1,2),facy,uygrad(1,1,2,i))
1225             call unormderiv(uz(1,i),uzder(1,1,1),fac,uzgrad(1,1,1,i))
1226             call unormderiv(uz(1,i),uzder(1,1,2),fac,uzgrad(1,1,2,i))
1227             endif
1228           else
1229 C Other residues
1230 C Compute the Z-axis
1231             call vecpr(dc_norm(1,i),dc_norm(1,i+1),uz(1,i))
1232             costh=dcos(pi-theta(i+2))
1233             fac=1.0d0/dsqrt(1.0d0-costh*costh)
1234             do k=1,3
1235               uz(k,i)=fac*uz(k,i)
1236             enddo
1237             if (calc_grad) then
1238 C Compute the derivatives of uz
1239             uzder(1,1,1)= 0.0d0
1240             uzder(2,1,1)=-dc_norm(3,i+1)
1241             uzder(3,1,1)= dc_norm(2,i+1)
1242             uzder(1,2,1)= dc_norm(3,i+1)
1243             uzder(2,2,1)= 0.0d0
1244             uzder(3,2,1)=-dc_norm(1,i+1)
1245             uzder(1,3,1)=-dc_norm(2,i+1)
1246             uzder(2,3,1)= dc_norm(1,i+1)
1247             uzder(3,3,1)= 0.0d0
1248             uzder(1,1,2)= 0.0d0
1249             uzder(2,1,2)= dc_norm(3,i)
1250             uzder(3,1,2)=-dc_norm(2,i)
1251             uzder(1,2,2)=-dc_norm(3,i)
1252             uzder(2,2,2)= 0.0d0
1253             uzder(3,2,2)= dc_norm(1,i)
1254             uzder(1,3,2)= dc_norm(2,i)
1255             uzder(2,3,2)=-dc_norm(1,i)
1256             uzder(3,3,2)= 0.0d0
1257             endif
1258 C Compute the Y-axis
1259             facy=fac
1260             do k=1,3
1261               uy(k,i)=facy*(dc_norm(k,i+1)-costh*dc_norm(k,i))
1262             enddo
1263             if (calc_grad) then
1264 C Compute the derivatives of uy
1265             do j=1,3
1266               do k=1,3
1267                 uyder(k,j,1)=2*dc_norm(k,i+1)*dc_norm(j,i)
1268      &                        -dc_norm(k,i)*dc_norm(j,i+1)
1269                 uyder(k,j,2)=-dc_norm(j,i)*dc_norm(k,i)
1270               enddo
1271               uyder(j,j,1)=uyder(j,j,1)-costh
1272               uyder(j,j,2)=1.0d0+uyder(j,j,2)
1273             enddo
1274             do j=1,2
1275               do k=1,3
1276                 do l=1,3
1277                   uygrad(l,k,j,i)=uyder(l,k,j)
1278                   uzgrad(l,k,j,i)=uzder(l,k,j)
1279                 enddo
1280               enddo
1281             enddo
1282             call unormderiv(uy(1,i),uyder(1,1,1),facy,uygrad(1,1,1,i))
1283             call unormderiv(uy(1,i),uyder(1,1,2),facy,uygrad(1,1,2,i))
1284             call unormderiv(uz(1,i),uzder(1,1,1),fac,uzgrad(1,1,1,i))
1285             call unormderiv(uz(1,i),uzder(1,1,2),fac,uzgrad(1,1,2,i))
1286           endif
1287           endif
1288       enddo
1289       if (calc_grad) then
1290       do i=1,nres-1
1291         vbld_inv_temp(1)=vbld_inv(i+1)
1292         if (i.lt.nres-1) then
1293           vbld_inv_temp(2)=vbld_inv(i+2)
1294         else
1295           vbld_inv_temp(2)=vbld_inv(i)
1296         endif
1297         do j=1,2
1298           do k=1,3
1299             do l=1,3
1300               uygrad(l,k,j,i)=vbld_inv_temp(j)*uygrad(l,k,j,i)
1301               uzgrad(l,k,j,i)=vbld_inv_temp(j)*uzgrad(l,k,j,i)
1302             enddo
1303           enddo
1304         enddo
1305       enddo
1306       endif
1307       return
1308       end
1309 C-----------------------------------------------------------------------------
1310       subroutine vec_and_deriv_test
1311       implicit real*8 (a-h,o-z)
1312       include 'DIMENSIONS'
1313       include 'DIMENSIONS.ZSCOPT'
1314       include 'COMMON.IOUNITS'
1315       include 'COMMON.GEO'
1316       include 'COMMON.VAR'
1317       include 'COMMON.LOCAL'
1318       include 'COMMON.CHAIN'
1319       include 'COMMON.VECTORS'
1320       dimension uyder(3,3,2),uzder(3,3,2)
1321 C Compute the local reference systems. For reference system (i), the
1322 C X-axis points from CA(i) to CA(i+1), the Y axis is in the
1323 C CA(i)-CA(i+1)-CA(i+2) plane, and the Z axis is perpendicular to this plane.
1324       do i=1,nres-1
1325           if (i.eq.nres-1) then
1326 C Case of the last full residue
1327 C Compute the Z-axis
1328             call vecpr(dc_norm(1,i),dc_norm(1,i-1),uz(1,i))
1329             costh=dcos(pi-theta(nres))
1330             fac=1.0d0/dsqrt(1.0d0-costh*costh)
1331 c            write (iout,*) 'fac',fac,
1332 c     &        1.0d0/dsqrt(scalar(uz(1,i),uz(1,i)))
1333             fac=1.0d0/dsqrt(scalar(uz(1,i),uz(1,i)))
1334             do k=1,3
1335               uz(k,i)=fac*uz(k,i)
1336             enddo
1337 C Compute the derivatives of uz
1338             uzder(1,1,1)= 0.0d0
1339             uzder(2,1,1)=-dc_norm(3,i-1)
1340             uzder(3,1,1)= dc_norm(2,i-1)
1341             uzder(1,2,1)= dc_norm(3,i-1)
1342             uzder(2,2,1)= 0.0d0
1343             uzder(3,2,1)=-dc_norm(1,i-1)
1344             uzder(1,3,1)=-dc_norm(2,i-1)
1345             uzder(2,3,1)= dc_norm(1,i-1)
1346             uzder(3,3,1)= 0.0d0
1347             uzder(1,1,2)= 0.0d0
1348             uzder(2,1,2)= dc_norm(3,i)
1349             uzder(3,1,2)=-dc_norm(2,i)
1350             uzder(1,2,2)=-dc_norm(3,i)
1351             uzder(2,2,2)= 0.0d0
1352             uzder(3,2,2)= dc_norm(1,i)
1353             uzder(1,3,2)= dc_norm(2,i)
1354             uzder(2,3,2)=-dc_norm(1,i)
1355             uzder(3,3,2)= 0.0d0
1356 C Compute the Y-axis
1357             do k=1,3
1358               uy(k,i)=fac*(dc_norm(k,i-1)-costh*dc_norm(k,i))
1359             enddo
1360             facy=fac
1361             facy=1.0d0/dsqrt(scalar(dc_norm(1,i),dc_norm(1,i))*
1362      &       (scalar(dc_norm(1,i-1),dc_norm(1,i-1))**2-
1363      &        scalar(dc_norm(1,i),dc_norm(1,i-1))**2))
1364             do k=1,3
1365 c              uy(k,i)=facy*(dc_norm(k,i+1)-costh*dc_norm(k,i))
1366               uy(k,i)=
1367 c     &        facy*(
1368      &        dc_norm(k,i-1)*scalar(dc_norm(1,i),dc_norm(1,i))
1369      &        -scalar(dc_norm(1,i),dc_norm(1,i-1))*dc_norm(k,i)
1370 c     &        )
1371             enddo
1372 c            write (iout,*) 'facy',facy,
1373 c     &       1.0d0/dsqrt(scalar(uy(1,i),uy(1,i)))
1374             facy=1.0d0/dsqrt(scalar(uy(1,i),uy(1,i)))
1375             do k=1,3
1376               uy(k,i)=facy*uy(k,i)
1377             enddo
1378 C Compute the derivatives of uy
1379             do j=1,3
1380               do k=1,3
1381                 uyder(k,j,1)=2*dc_norm(k,i-1)*dc_norm(j,i)
1382      &                        -dc_norm(k,i)*dc_norm(j,i-1)
1383                 uyder(k,j,2)=-dc_norm(j,i)*dc_norm(k,i)
1384               enddo
1385 c              uyder(j,j,1)=uyder(j,j,1)-costh
1386 c              uyder(j,j,2)=1.0d0+uyder(j,j,2)
1387               uyder(j,j,1)=uyder(j,j,1)
1388      &          -scalar(dc_norm(1,i),dc_norm(1,i-1))
1389               uyder(j,j,2)=scalar(dc_norm(1,i),dc_norm(1,i))
1390      &          +uyder(j,j,2)
1391             enddo
1392             do j=1,2
1393               do k=1,3
1394                 do l=1,3
1395                   uygrad(l,k,j,i)=uyder(l,k,j)
1396                   uzgrad(l,k,j,i)=uzder(l,k,j)
1397                 enddo
1398               enddo
1399             enddo
1400             call unormderiv(uy(1,i),uyder(1,1,1),facy,uygrad(1,1,1,i))
1401             call unormderiv(uy(1,i),uyder(1,1,2),facy,uygrad(1,1,2,i))
1402             call unormderiv(uz(1,i),uzder(1,1,1),fac,uzgrad(1,1,1,i))
1403             call unormderiv(uz(1,i),uzder(1,1,2),fac,uzgrad(1,1,2,i))
1404           else
1405 C Other residues
1406 C Compute the Z-axis
1407             call vecpr(dc_norm(1,i),dc_norm(1,i+1),uz(1,i))
1408             costh=dcos(pi-theta(i+2))
1409             fac=1.0d0/dsqrt(1.0d0-costh*costh)
1410             fac=1.0d0/dsqrt(scalar(uz(1,i),uz(1,i)))
1411             do k=1,3
1412               uz(k,i)=fac*uz(k,i)
1413             enddo
1414 C Compute the derivatives of uz
1415             uzder(1,1,1)= 0.0d0
1416             uzder(2,1,1)=-dc_norm(3,i+1)
1417             uzder(3,1,1)= dc_norm(2,i+1)
1418             uzder(1,2,1)= dc_norm(3,i+1)
1419             uzder(2,2,1)= 0.0d0
1420             uzder(3,2,1)=-dc_norm(1,i+1)
1421             uzder(1,3,1)=-dc_norm(2,i+1)
1422             uzder(2,3,1)= dc_norm(1,i+1)
1423             uzder(3,3,1)= 0.0d0
1424             uzder(1,1,2)= 0.0d0
1425             uzder(2,1,2)= dc_norm(3,i)
1426             uzder(3,1,2)=-dc_norm(2,i)
1427             uzder(1,2,2)=-dc_norm(3,i)
1428             uzder(2,2,2)= 0.0d0
1429             uzder(3,2,2)= dc_norm(1,i)
1430             uzder(1,3,2)= dc_norm(2,i)
1431             uzder(2,3,2)=-dc_norm(1,i)
1432             uzder(3,3,2)= 0.0d0
1433 C Compute the Y-axis
1434             facy=fac
1435             facy=1.0d0/dsqrt(scalar(dc_norm(1,i),dc_norm(1,i))*
1436      &       (scalar(dc_norm(1,i+1),dc_norm(1,i+1))**2-
1437      &        scalar(dc_norm(1,i),dc_norm(1,i+1))**2))
1438             do k=1,3
1439 c              uy(k,i)=facy*(dc_norm(k,i+1)-costh*dc_norm(k,i))
1440               uy(k,i)=
1441 c     &        facy*(
1442      &        dc_norm(k,i+1)*scalar(dc_norm(1,i),dc_norm(1,i))
1443      &        -scalar(dc_norm(1,i),dc_norm(1,i+1))*dc_norm(k,i)
1444 c     &        )
1445             enddo
1446 c            write (iout,*) 'facy',facy,
1447 c     &       1.0d0/dsqrt(scalar(uy(1,i),uy(1,i)))
1448             facy=1.0d0/dsqrt(scalar(uy(1,i),uy(1,i)))
1449             do k=1,3
1450               uy(k,i)=facy*uy(k,i)
1451             enddo
1452 C Compute the derivatives of uy
1453             do j=1,3
1454               do k=1,3
1455                 uyder(k,j,1)=2*dc_norm(k,i+1)*dc_norm(j,i)
1456      &                        -dc_norm(k,i)*dc_norm(j,i+1)
1457                 uyder(k,j,2)=-dc_norm(j,i)*dc_norm(k,i)
1458               enddo
1459 c              uyder(j,j,1)=uyder(j,j,1)-costh
1460 c              uyder(j,j,2)=1.0d0+uyder(j,j,2)
1461               uyder(j,j,1)=uyder(j,j,1)
1462      &          -scalar(dc_norm(1,i),dc_norm(1,i+1))
1463               uyder(j,j,2)=scalar(dc_norm(1,i),dc_norm(1,i))
1464      &          +uyder(j,j,2)
1465             enddo
1466             do j=1,2
1467               do k=1,3
1468                 do l=1,3
1469                   uygrad(l,k,j,i)=uyder(l,k,j)
1470                   uzgrad(l,k,j,i)=uzder(l,k,j)
1471                 enddo
1472               enddo
1473             enddo
1474             call unormderiv(uy(1,i),uyder(1,1,1),facy,uygrad(1,1,1,i))
1475             call unormderiv(uy(1,i),uyder(1,1,2),facy,uygrad(1,1,2,i))
1476             call unormderiv(uz(1,i),uzder(1,1,1),fac,uzgrad(1,1,1,i))
1477             call unormderiv(uz(1,i),uzder(1,1,2),fac,uzgrad(1,1,2,i))
1478           endif
1479       enddo
1480       do i=1,nres-1
1481         do j=1,2
1482           do k=1,3
1483             do l=1,3
1484               uygrad(l,k,j,i)=vblinv*uygrad(l,k,j,i)
1485               uzgrad(l,k,j,i)=vblinv*uzgrad(l,k,j,i)
1486             enddo
1487           enddo
1488         enddo
1489       enddo
1490       return
1491       end
1492 C-----------------------------------------------------------------------------
1493       subroutine check_vecgrad
1494       implicit real*8 (a-h,o-z)
1495       include 'DIMENSIONS'
1496       include 'DIMENSIONS.ZSCOPT'
1497       include 'COMMON.IOUNITS'
1498       include 'COMMON.GEO'
1499       include 'COMMON.VAR'
1500       include 'COMMON.LOCAL'
1501       include 'COMMON.CHAIN'
1502       include 'COMMON.VECTORS'
1503       dimension uygradt(3,3,2,maxres),uzgradt(3,3,2,maxres)
1504       dimension uyt(3,maxres),uzt(3,maxres)
1505       dimension uygradn(3,3,2),uzgradn(3,3,2),erij(3)
1506       double precision delta /1.0d-7/
1507       call vec_and_deriv
1508 cd      do i=1,nres
1509 crc          write(iout,'(2i5,2(3f10.5,5x))') i,1,dc_norm(:,i)
1510 crc          write(iout,'(2i5,2(3f10.5,5x))') i,2,uy(:,i)
1511 crc          write(iout,'(2i5,2(3f10.5,5x)/)')i,3,uz(:,i)
1512 cd          write(iout,'(2i5,2(3f10.5,5x))') i,1,
1513 cd     &     (dc_norm(if90,i),if90=1,3)
1514 cd          write(iout,'(2i5,2(3f10.5,5x))') i,2,(uy(if90,i),if90=1,3)
1515 cd          write(iout,'(2i5,2(3f10.5,5x)/)')i,3,(uz(if90,i),if90=1,3)
1516 cd          write(iout,'(a)')
1517 cd      enddo
1518       do i=1,nres
1519         do j=1,2
1520           do k=1,3
1521             do l=1,3
1522               uygradt(l,k,j,i)=uygrad(l,k,j,i)
1523               uzgradt(l,k,j,i)=uzgrad(l,k,j,i)
1524             enddo
1525           enddo
1526         enddo
1527       enddo
1528       call vec_and_deriv
1529       do i=1,nres
1530         do j=1,3
1531           uyt(j,i)=uy(j,i)
1532           uzt(j,i)=uz(j,i)
1533         enddo
1534       enddo
1535       do i=1,nres
1536 cd        write (iout,*) 'i=',i
1537         do k=1,3
1538           erij(k)=dc_norm(k,i)
1539         enddo
1540         do j=1,3
1541           do k=1,3
1542             dc_norm(k,i)=erij(k)
1543           enddo
1544           dc_norm(j,i)=dc_norm(j,i)+delta
1545 c          fac=dsqrt(scalar(dc_norm(1,i),dc_norm(1,i)))
1546 c          do k=1,3
1547 c            dc_norm(k,i)=dc_norm(k,i)/fac
1548 c          enddo
1549 c          write (iout,*) (dc_norm(k,i),k=1,3)
1550 c          write (iout,*) (erij(k),k=1,3)
1551           call vec_and_deriv
1552           do k=1,3
1553             uygradn(k,j,1)=(uy(k,i)-uyt(k,i))/delta
1554             uygradn(k,j,2)=(uy(k,i-1)-uyt(k,i-1))/delta
1555             uzgradn(k,j,1)=(uz(k,i)-uzt(k,i))/delta
1556             uzgradn(k,j,2)=(uz(k,i-1)-uzt(k,i-1))/delta
1557           enddo
1558 c          write (iout,'(i5,3f8.5,3x,3f8.5,5x,3f8.5,3x,3f8.5)')
1559 c     &      j,(uzgradt(k,j,1,i),k=1,3),(uzgradn(k,j,1),k=1,3),
1560 c     &      (uzgradt(k,j,2,i-1),k=1,3),(uzgradn(k,j,2),k=1,3)
1561         enddo
1562         do k=1,3
1563           dc_norm(k,i)=erij(k)
1564         enddo
1565 cd        do k=1,3
1566 cd          write (iout,'(i5,3f8.5,3x,3f8.5,5x,3f8.5,3x,3f8.5)')
1567 cd     &      k,(uygradt(k,l,1,i),l=1,3),(uygradn(k,l,1),l=1,3),
1568 cd     &      (uygradt(k,l,2,i-1),l=1,3),(uygradn(k,l,2),l=1,3)
1569 cd          write (iout,'(i5,3f8.5,3x,3f8.5,5x,3f8.5,3x,3f8.5)')
1570 cd     &      k,(uzgradt(k,l,1,i),l=1,3),(uzgradn(k,l,1),l=1,3),
1571 cd     &      (uzgradt(k,l,2,i-1),l=1,3),(uzgradn(k,l,2),l=1,3)
1572 cd          write (iout,'(a)')
1573 cd        enddo
1574       enddo
1575       return
1576       end
1577 C--------------------------------------------------------------------------
1578       subroutine set_matrices
1579       implicit real*8 (a-h,o-z)
1580       include 'DIMENSIONS'
1581       include 'DIMENSIONS.ZSCOPT'
1582       include 'COMMON.IOUNITS'
1583       include 'COMMON.GEO'
1584       include 'COMMON.VAR'
1585       include 'COMMON.LOCAL'
1586       include 'COMMON.CHAIN'
1587       include 'COMMON.DERIV'
1588       include 'COMMON.INTERACT'
1589       include 'COMMON.CONTACTS'
1590       include 'COMMON.TORSION'
1591       include 'COMMON.VECTORS'
1592       include 'COMMON.FFIELD'
1593       double precision auxvec(2),auxmat(2,2)
1594 C
1595 C Compute the virtual-bond-torsional-angle dependent quantities needed
1596 C to calculate the el-loc multibody terms of various order.
1597 C
1598       do i=3,nres+1
1599         if (i .lt. nres+1) then
1600           sin1=dsin(phi(i))
1601           cos1=dcos(phi(i))
1602           sintab(i-2)=sin1
1603           costab(i-2)=cos1
1604           obrot(1,i-2)=cos1
1605           obrot(2,i-2)=sin1
1606           sin2=dsin(2*phi(i))
1607           cos2=dcos(2*phi(i))
1608           sintab2(i-2)=sin2
1609           costab2(i-2)=cos2
1610           obrot2(1,i-2)=cos2
1611           obrot2(2,i-2)=sin2
1612           Ug(1,1,i-2)=-cos1
1613           Ug(1,2,i-2)=-sin1
1614           Ug(2,1,i-2)=-sin1
1615           Ug(2,2,i-2)= cos1
1616           Ug2(1,1,i-2)=-cos2
1617           Ug2(1,2,i-2)=-sin2
1618           Ug2(2,1,i-2)=-sin2
1619           Ug2(2,2,i-2)= cos2
1620         else
1621           costab(i-2)=1.0d0
1622           sintab(i-2)=0.0d0
1623           obrot(1,i-2)=1.0d0
1624           obrot(2,i-2)=0.0d0
1625           obrot2(1,i-2)=0.0d0
1626           obrot2(2,i-2)=0.0d0
1627           Ug(1,1,i-2)=1.0d0
1628           Ug(1,2,i-2)=0.0d0
1629           Ug(2,1,i-2)=0.0d0
1630           Ug(2,2,i-2)=1.0d0
1631           Ug2(1,1,i-2)=0.0d0
1632           Ug2(1,2,i-2)=0.0d0
1633           Ug2(2,1,i-2)=0.0d0
1634           Ug2(2,2,i-2)=0.0d0
1635         endif
1636         if (i .gt. 3 .and. i .lt. nres+1) then
1637           obrot_der(1,i-2)=-sin1
1638           obrot_der(2,i-2)= cos1
1639           Ugder(1,1,i-2)= sin1
1640           Ugder(1,2,i-2)=-cos1
1641           Ugder(2,1,i-2)=-cos1
1642           Ugder(2,2,i-2)=-sin1
1643           dwacos2=cos2+cos2
1644           dwasin2=sin2+sin2
1645           obrot2_der(1,i-2)=-dwasin2
1646           obrot2_der(2,i-2)= dwacos2
1647           Ug2der(1,1,i-2)= dwasin2
1648           Ug2der(1,2,i-2)=-dwacos2
1649           Ug2der(2,1,i-2)=-dwacos2
1650           Ug2der(2,2,i-2)=-dwasin2
1651         else
1652           obrot_der(1,i-2)=0.0d0
1653           obrot_der(2,i-2)=0.0d0
1654           Ugder(1,1,i-2)=0.0d0
1655           Ugder(1,2,i-2)=0.0d0
1656           Ugder(2,1,i-2)=0.0d0
1657           Ugder(2,2,i-2)=0.0d0
1658           obrot2_der(1,i-2)=0.0d0
1659           obrot2_der(2,i-2)=0.0d0
1660           Ug2der(1,1,i-2)=0.0d0
1661           Ug2der(1,2,i-2)=0.0d0
1662           Ug2der(2,1,i-2)=0.0d0
1663           Ug2der(2,2,i-2)=0.0d0
1664         endif
1665         if (i.gt. iatel_s+2 .and. i.lt.iatel_e+5) then
1666           iti = itortyp(itype(i-2))
1667         else
1668           iti=ntortyp+1
1669         endif
1670         if (i.gt. iatel_s+1 .and. i.lt.iatel_e+4) then
1671           iti1 = itortyp(itype(i-1))
1672         else
1673           iti1=ntortyp+1
1674         endif
1675 cd        write (iout,*) '*******i',i,' iti1',iti
1676 cd        write (iout,*) 'b1',b1(:,iti)
1677 cd        write (iout,*) 'b2',b2(:,iti)
1678 cd        write (iout,*) 'Ug',Ug(:,:,i-2)
1679         if (i .gt. iatel_s+2) then
1680           call matvec2(Ug(1,1,i-2),b2(1,iti),Ub2(1,i-2))
1681           call matmat2(EE(1,1,iti),Ug(1,1,i-2),EUg(1,1,i-2))
1682           call matmat2(CC(1,1,iti),Ug(1,1,i-2),CUg(1,1,i-2))
1683           call matmat2(DD(1,1,iti),Ug(1,1,i-2),DUg(1,1,i-2))
1684           call matmat2(Dtilde(1,1,iti),Ug2(1,1,i-2),DtUg2(1,1,i-2))
1685           call matvec2(Ctilde(1,1,iti1),obrot(1,i-2),Ctobr(1,i-2))
1686           call matvec2(Dtilde(1,1,iti),obrot2(1,i-2),Dtobr2(1,i-2))
1687         else
1688           do k=1,2
1689             Ub2(k,i-2)=0.0d0
1690             Ctobr(k,i-2)=0.0d0
1691             Dtobr2(k,i-2)=0.0d0
1692             do l=1,2
1693               EUg(l,k,i-2)=0.0d0
1694               CUg(l,k,i-2)=0.0d0
1695               DUg(l,k,i-2)=0.0d0
1696               DtUg2(l,k,i-2)=0.0d0
1697             enddo
1698           enddo
1699         endif
1700         call matvec2(Ugder(1,1,i-2),b2(1,iti),Ub2der(1,i-2))
1701         call matmat2(EE(1,1,iti),Ugder(1,1,i-2),EUgder(1,1,i-2))
1702         call matmat2(CC(1,1,iti1),Ugder(1,1,i-2),CUgder(1,1,i-2))
1703         call matmat2(DD(1,1,iti),Ugder(1,1,i-2),DUgder(1,1,i-2))
1704         call matmat2(Dtilde(1,1,iti),Ug2der(1,1,i-2),DtUg2der(1,1,i-2))
1705         call matvec2(Ctilde(1,1,iti1),obrot_der(1,i-2),Ctobrder(1,i-2))
1706         call matvec2(Dtilde(1,1,iti),obrot2_der(1,i-2),Dtobr2der(1,i-2))
1707         do k=1,2
1708           muder(k,i-2)=Ub2der(k,i-2)
1709         enddo
1710         if (i.gt. iatel_s+1 .and. i.lt.iatel_e+4) then
1711           iti1 = itortyp(itype(i-1))
1712         else
1713           iti1=ntortyp+1
1714         endif
1715         do k=1,2
1716           mu(k,i-2)=Ub2(k,i-2)+b1(k,iti1)
1717         enddo
1718 C Vectors and matrices dependent on a single virtual-bond dihedral.
1719         call matvec2(DD(1,1,iti),b1tilde(1,iti1),auxvec(1))
1720         call matvec2(Ug2(1,1,i-2),auxvec(1),Ug2Db1t(1,i-2))
1721         call matvec2(Ug2der(1,1,i-2),auxvec(1),Ug2Db1tder(1,i-2))
1722         call matvec2(CC(1,1,iti1),Ub2(1,i-2),CUgb2(1,i-2))
1723         call matvec2(CC(1,1,iti1),Ub2der(1,i-2),CUgb2der(1,i-2))
1724         call matmat2(EUg(1,1,i-2),CC(1,1,iti1),EUgC(1,1,i-2))
1725         call matmat2(EUgder(1,1,i-2),CC(1,1,iti1),EUgCder(1,1,i-2))
1726         call matmat2(EUg(1,1,i-2),DD(1,1,iti1),EUgD(1,1,i-2))
1727         call matmat2(EUgder(1,1,i-2),DD(1,1,iti1),EUgDder(1,1,i-2))
1728 cd        write (iout,*) 'i',i,' mu ',(mu(k,i-2),k=1,2),
1729 cd     &  ' mu1',(b1(k,i-2),k=1,2),' mu2',(Ub2(k,i-2),k=1,2)
1730       enddo
1731 C Matrices dependent on two consecutive virtual-bond dihedrals.
1732 C The order of matrices is from left to right.
1733       do i=2,nres-1
1734         call matmat2(DtUg2(1,1,i-1),EUg(1,1,i),DtUg2EUg(1,1,i))
1735         call matmat2(DtUg2der(1,1,i-1),EUg(1,1,i),DtUg2EUgder(1,1,1,i))
1736         call matmat2(DtUg2(1,1,i-1),EUgder(1,1,i),DtUg2EUgder(1,1,2,i))
1737         call transpose2(DtUg2(1,1,i-1),auxmat(1,1))
1738         call matmat2(auxmat(1,1),EUg(1,1,i),Ug2DtEUg(1,1,i))
1739         call matmat2(auxmat(1,1),EUgder(1,1,i),Ug2DtEUgder(1,1,2,i))
1740         call transpose2(DtUg2der(1,1,i-1),auxmat(1,1))
1741         call matmat2(auxmat(1,1),EUg(1,1,i),Ug2DtEUgder(1,1,1,i))
1742       enddo
1743 cd      do i=1,nres
1744 cd        iti = itortyp(itype(i))
1745 cd        write (iout,*) i
1746 cd        do j=1,2
1747 cd        write (iout,'(2f10.5,5x,2f10.5,5x,2f10.5)')
1748 cd     &  (EE(j,k,iti),k=1,2),(Ug(j,k,i),k=1,2),(EUg(j,k,i),k=1,2)
1749 cd        enddo
1750 cd      enddo
1751       return
1752       end
1753 C--------------------------------------------------------------------------
1754       subroutine eelec(ees,evdw1,eel_loc,eello_turn3,eello_turn4)
1755 C
1756 C This subroutine calculates the average interaction energy and its gradient
1757 C in the virtual-bond vectors between non-adjacent peptide groups, based on
1758 C the potential described in Liwo et al., Protein Sci., 1993, 2, 1715.
1759 C The potential depends both on the distance of peptide-group centers and on
1760 C the orientation of the CA-CA virtual bonds.
1761 C
1762       implicit real*8 (a-h,o-z)
1763       include 'DIMENSIONS'
1764       include 'DIMENSIONS.ZSCOPT'
1765       include 'COMMON.CONTROL'
1766       include 'COMMON.IOUNITS'
1767       include 'COMMON.GEO'
1768       include 'COMMON.VAR'
1769       include 'COMMON.LOCAL'
1770       include 'COMMON.CHAIN'
1771       include 'COMMON.DERIV'
1772       include 'COMMON.INTERACT'
1773       include 'COMMON.CONTACTS'
1774       include 'COMMON.TORSION'
1775       include 'COMMON.VECTORS'
1776       include 'COMMON.FFIELD'
1777       dimension ggg(3),gggp(3),gggm(3),erij(3),dcosb(3),dcosg(3),
1778      &          erder(3,3),uryg(3,3),urzg(3,3),vryg(3,3),vrzg(3,3)
1779       double precision acipa(2,2),agg(3,4),aggi(3,4),aggi1(3,4),
1780      &    aggj(3,4),aggj1(3,4),a_temp(2,2),muij(4)
1781       common /locel/ a_temp,agg,aggi,aggi1,aggj,aggj1,j1
1782 c 4/26/02 - AL scaling factor for 1,4 repulsive VDW interactions
1783       double precision scal_el /0.5d0/
1784 C 12/13/98
1785 C 13-go grudnia roku pamietnego...
1786       double precision unmat(3,3) /1.0d0,0.0d0,0.0d0,
1787      &                   0.0d0,1.0d0,0.0d0,
1788      &                   0.0d0,0.0d0,1.0d0/
1789 cd      write(iout,*) 'In EELEC'
1790 cd      do i=1,nloctyp
1791 cd        write(iout,*) 'Type',i
1792 cd        write(iout,*) 'B1',B1(:,i)
1793 cd        write(iout,*) 'B2',B2(:,i)
1794 cd        write(iout,*) 'CC',CC(:,:,i)
1795 cd        write(iout,*) 'DD',DD(:,:,i)
1796 cd        write(iout,*) 'EE',EE(:,:,i)
1797 cd      enddo
1798 cd      call check_vecgrad
1799 cd      stop
1800       if (icheckgrad.eq.1) then
1801         do i=1,nres-1
1802           fac=1.0d0/dsqrt(scalar(dc(1,i),dc(1,i)))
1803           do k=1,3
1804             dc_norm(k,i)=dc(k,i)*fac
1805           enddo
1806 c          write (iout,*) 'i',i,' fac',fac
1807         enddo
1808       endif
1809       if (wel_loc.gt.0.0d0 .or. wcorr4.gt.0.0d0 .or. wcorr5.gt.0.0d0
1810      &    .or. wcorr6.gt.0.0d0 .or. wturn3.gt.0.0d0 .or.
1811      &    wturn4.gt.0.0d0 .or. wturn6.gt.0.0d0) then
1812 cd      if (wel_loc.gt.0.0d0) then
1813         if (icheckgrad.eq.1) then
1814         call vec_and_deriv_test
1815         else
1816         call vec_and_deriv
1817         endif
1818         call set_matrices
1819       endif
1820 cd      do i=1,nres-1
1821 cd        write (iout,*) 'i=',i
1822 cd        do k=1,3
1823 cd          write (iout,'(i5,2f10.5)') k,uy(k,i),uz(k,i)
1824 cd        enddo
1825 cd        do k=1,3
1826 cd          write (iout,'(f10.5,2x,3f10.5,2x,3f10.5)')
1827 cd     &     uz(k,i),(uzgrad(k,l,1,i),l=1,3),(uzgrad(k,l,2,i),l=1,3)
1828 cd        enddo
1829 cd      enddo
1830       num_conti_hb=0
1831       ees=0.0D0
1832       evdw1=0.0D0
1833       eel_loc=0.0d0
1834       eello_turn3=0.0d0
1835       eello_turn4=0.0d0
1836       ind=0
1837       do i=1,nres
1838         num_cont_hb(i)=0
1839       enddo
1840 cd      print '(a)','Enter EELEC'
1841 cd      write (iout,*) 'iatel_s=',iatel_s,' iatel_e=',iatel_e
1842       do i=1,nres
1843         gel_loc_loc(i)=0.0d0
1844         gcorr_loc(i)=0.0d0
1845       enddo
1846       do i=iatel_s,iatel_e
1847         if (itel(i).eq.0) goto 1215
1848         dxi=dc(1,i)
1849         dyi=dc(2,i)
1850         dzi=dc(3,i)
1851         dx_normi=dc_norm(1,i)
1852         dy_normi=dc_norm(2,i)
1853         dz_normi=dc_norm(3,i)
1854         xmedi=c(1,i)+0.5d0*dxi
1855         ymedi=c(2,i)+0.5d0*dyi
1856         zmedi=c(3,i)+0.5d0*dzi
1857         num_conti=0
1858 c        write (iout,*) 'i',i,' ielstart',ielstart(i),' ielend',ielend(i)
1859         do j=ielstart(i),ielend(i)
1860           if (itel(j).eq.0) goto 1216
1861           ind=ind+1
1862           iteli=itel(i)
1863           itelj=itel(j)
1864           if (j.eq.i+2 .and. itelj.eq.2) iteli=2
1865           aaa=app(iteli,itelj)
1866           bbb=bpp(iteli,itelj)
1867 C Diagnostics only!!!
1868 c         aaa=0.0D0
1869 c         bbb=0.0D0
1870 c         ael6i=0.0D0
1871 c         ael3i=0.0D0
1872 C End diagnostics
1873           ael6i=ael6(iteli,itelj)
1874           ael3i=ael3(iteli,itelj)
1875           dxj=dc(1,j)
1876           dyj=dc(2,j)
1877           dzj=dc(3,j)
1878           dx_normj=dc_norm(1,j)
1879           dy_normj=dc_norm(2,j)
1880           dz_normj=dc_norm(3,j)
1881           xj=c(1,j)+0.5D0*dxj-xmedi
1882           yj=c(2,j)+0.5D0*dyj-ymedi
1883           zj=c(3,j)+0.5D0*dzj-zmedi
1884           rij=xj*xj+yj*yj+zj*zj
1885           rrmij=1.0D0/rij
1886           rij=dsqrt(rij)
1887           rmij=1.0D0/rij
1888           r3ij=rrmij*rmij
1889           r6ij=r3ij*r3ij
1890           cosa=dx_normi*dx_normj+dy_normi*dy_normj+dz_normi*dz_normj
1891           cosb=(xj*dx_normi+yj*dy_normi+zj*dz_normi)*rmij
1892           cosg=(xj*dx_normj+yj*dy_normj+zj*dz_normj)*rmij
1893           fac=cosa-3.0D0*cosb*cosg
1894           ev1=aaa*r6ij*r6ij
1895 c 4/26/02 - AL scaling down 1,4 repulsive VDW interactions
1896           if (j.eq.i+2) ev1=scal_el*ev1
1897           ev2=bbb*r6ij
1898           fac3=ael6i*r6ij
1899           fac4=ael3i*r3ij
1900           evdwij=ev1+ev2
1901           el1=fac3*(4.0D0+fac*fac-3.0D0*(cosb*cosb+cosg*cosg))
1902           el2=fac4*fac
1903           eesij=el1+el2
1904 c          write (iout,*) "i",i,iteli," j",j,itelj," eesij",eesij
1905 C 12/26/95 - for the evaluation of multi-body H-bonding interactions
1906           ees0ij=4.0D0+fac*fac-3.0D0*(cosb*cosb+cosg*cosg)
1907           ees=ees+eesij
1908           evdw1=evdw1+evdwij
1909 cd          write(iout,'(2(2i3,2x),7(1pd12.4)/2(3(1pd12.4),5x)/)')
1910 cd     &      iteli,i,itelj,j,aaa,bbb,ael6i,ael3i,
1911 cd     &      1.0D0/dsqrt(rrmij),evdwij,eesij,
1912 cd     &      xmedi,ymedi,zmedi,xj,yj,zj
1913 C
1914 C Calculate contributions to the Cartesian gradient.
1915 C
1916 #ifdef SPLITELE
1917           facvdw=-6*rrmij*(ev1+evdwij)
1918           facel=-3*rrmij*(el1+eesij)
1919           fac1=fac
1920           erij(1)=xj*rmij
1921           erij(2)=yj*rmij
1922           erij(3)=zj*rmij
1923           if (calc_grad) then
1924 *
1925 * Radial derivatives. First process both termini of the fragment (i,j)
1926 *
1927           ggg(1)=facel*xj
1928           ggg(2)=facel*yj
1929           ggg(3)=facel*zj
1930           do k=1,3
1931             ghalf=0.5D0*ggg(k)
1932             gelc(k,i)=gelc(k,i)+ghalf
1933             gelc(k,j)=gelc(k,j)+ghalf
1934           enddo
1935 *
1936 * Loop over residues i+1 thru j-1.
1937 *
1938           do k=i+1,j-1
1939             do l=1,3
1940               gelc(l,k)=gelc(l,k)+ggg(l)
1941             enddo
1942           enddo
1943           ggg(1)=facvdw*xj
1944           ggg(2)=facvdw*yj
1945           ggg(3)=facvdw*zj
1946           do k=1,3
1947             ghalf=0.5D0*ggg(k)
1948             gvdwpp(k,i)=gvdwpp(k,i)+ghalf
1949             gvdwpp(k,j)=gvdwpp(k,j)+ghalf
1950           enddo
1951 *
1952 * Loop over residues i+1 thru j-1.
1953 *
1954           do k=i+1,j-1
1955             do l=1,3
1956               gvdwpp(l,k)=gvdwpp(l,k)+ggg(l)
1957             enddo
1958           enddo
1959 #else
1960           facvdw=ev1+evdwij
1961           facel=el1+eesij
1962           fac1=fac
1963           fac=-3*rrmij*(facvdw+facvdw+facel)
1964           erij(1)=xj*rmij
1965           erij(2)=yj*rmij
1966           erij(3)=zj*rmij
1967           if (calc_grad) then
1968 *
1969 * Radial derivatives. First process both termini of the fragment (i,j)
1970 *
1971           ggg(1)=fac*xj
1972           ggg(2)=fac*yj
1973           ggg(3)=fac*zj
1974           do k=1,3
1975             ghalf=0.5D0*ggg(k)
1976             gelc(k,i)=gelc(k,i)+ghalf
1977             gelc(k,j)=gelc(k,j)+ghalf
1978           enddo
1979 *
1980 * Loop over residues i+1 thru j-1.
1981 *
1982           do k=i+1,j-1
1983             do l=1,3
1984               gelc(l,k)=gelc(l,k)+ggg(l)
1985             enddo
1986           enddo
1987 #endif
1988 *
1989 * Angular part
1990 *
1991           ecosa=2.0D0*fac3*fac1+fac4
1992           fac4=-3.0D0*fac4
1993           fac3=-6.0D0*fac3
1994           ecosb=(fac3*(fac1*cosg+cosb)+cosg*fac4)
1995           ecosg=(fac3*(fac1*cosb+cosg)+cosb*fac4)
1996           do k=1,3
1997             dcosb(k)=rmij*(dc_norm(k,i)-erij(k)*cosb)
1998             dcosg(k)=rmij*(dc_norm(k,j)-erij(k)*cosg)
1999           enddo
2000 cd        print '(2i3,2(3(1pd14.5),3x))',i,j,(dcosb(k),k=1,3),
2001 cd   &          (dcosg(k),k=1,3)
2002           do k=1,3
2003             ggg(k)=ecosb*dcosb(k)+ecosg*dcosg(k)
2004           enddo
2005           do k=1,3
2006             ghalf=0.5D0*ggg(k)
2007             gelc(k,i)=gelc(k,i)+ghalf
2008      &               +(ecosa*(dc_norm(k,j)-cosa*dc_norm(k,i))
2009      &               + ecosb*(erij(k)-cosb*dc_norm(k,i)))*vbld_inv(i+1)
2010             gelc(k,j)=gelc(k,j)+ghalf
2011      &               +(ecosa*(dc_norm(k,i)-cosa*dc_norm(k,j))
2012      &               + ecosg*(erij(k)-cosg*dc_norm(k,j)))*vbld_inv(j+1)
2013           enddo
2014           do k=i+1,j-1
2015             do l=1,3
2016               gelc(l,k)=gelc(l,k)+ggg(l)
2017             enddo
2018           enddo
2019           endif
2020
2021           IF (wel_loc.gt.0.0d0 .or. wcorr4.gt.0.0d0 .or. wcorr5.gt.0.0d0
2022      &        .or. wcorr6.gt.0.0d0 .or. wturn3.gt.0.0d0
2023      &        .or. wturn4.gt.0.0d0 .or. wturn6.gt.0.0d0) THEN
2024 C
2025 C 9/25/99 Mixed third-order local-electrostatic terms. The local-interaction
2026 C   energy of a peptide unit is assumed in the form of a second-order
2027 C   Fourier series in the angles lambda1 and lambda2 (see Nishikawa et al.
2028 C   Macromolecules, 1974, 7, 797-806 for definition). This correlation terms
2029 C   are computed for EVERY pair of non-contiguous peptide groups.
2030 C
2031           if (j.lt.nres-1) then
2032             j1=j+1
2033             j2=j-1
2034           else
2035             j1=j-1
2036             j2=j-2
2037           endif
2038           kkk=0
2039           do k=1,2
2040             do l=1,2
2041               kkk=kkk+1
2042               muij(kkk)=mu(k,i)*mu(l,j)
2043             enddo
2044           enddo
2045 cd         write (iout,*) 'EELEC: i',i,' j',j
2046 cd          write (iout,*) 'j',j,' j1',j1,' j2',j2
2047 cd          write(iout,*) 'muij',muij
2048           ury=scalar(uy(1,i),erij)
2049           urz=scalar(uz(1,i),erij)
2050           vry=scalar(uy(1,j),erij)
2051           vrz=scalar(uz(1,j),erij)
2052           a22=scalar(uy(1,i),uy(1,j))-3*ury*vry
2053           a23=scalar(uy(1,i),uz(1,j))-3*ury*vrz
2054           a32=scalar(uz(1,i),uy(1,j))-3*urz*vry
2055           a33=scalar(uz(1,i),uz(1,j))-3*urz*vrz
2056 C For diagnostics only
2057 cd          a22=1.0d0
2058 cd          a23=1.0d0
2059 cd          a32=1.0d0
2060 cd          a33=1.0d0
2061           fac=dsqrt(-ael6i)*r3ij
2062 cd          write (2,*) 'fac=',fac
2063 C For diagnostics only
2064 cd          fac=1.0d0
2065           a22=a22*fac
2066           a23=a23*fac
2067           a32=a32*fac
2068           a33=a33*fac
2069 cd          write (iout,'(4i5,4f10.5)')
2070 cd     &     i,itortyp(itype(i)),j,itortyp(itype(j)),a22,a23,a32,a33
2071 cd          write (iout,'(6f10.5)') (muij(k),k=1,4),fac,eel_loc_ij
2072 cd          write (iout,'(2(3f10.5,5x)/2(3f10.5,5x))') (uy(k,i),k=1,3),
2073 cd     &      (uz(k,i),k=1,3),(uy(k,j),k=1,3),(uz(k,j),k=1,3)
2074 cd          write (iout,'(4f10.5)')
2075 cd     &      scalar(uy(1,i),uy(1,j)),scalar(uy(1,i),uz(1,j)),
2076 cd     &      scalar(uz(1,i),uy(1,j)),scalar(uz(1,i),uz(1,j))
2077 cd          write (iout,'(4f10.5)') ury,urz,vry,vrz
2078 cd           write (iout,'(2i3,9f10.5/)') i,j,
2079 cd     &      fac22,a22,fac23,a23,fac32,a32,fac33,a33,eel_loc_ij
2080           if (calc_grad) then
2081 C Derivatives of the elements of A in virtual-bond vectors
2082           call unormderiv(erij(1),unmat(1,1),rmij,erder(1,1))
2083 cd          do k=1,3
2084 cd            do l=1,3
2085 cd              erder(k,l)=0.0d0
2086 cd            enddo
2087 cd          enddo
2088           do k=1,3
2089             uryg(k,1)=scalar(erder(1,k),uy(1,i))
2090             uryg(k,2)=scalar(uygrad(1,k,1,i),erij(1))
2091             uryg(k,3)=scalar(uygrad(1,k,2,i),erij(1))
2092             urzg(k,1)=scalar(erder(1,k),uz(1,i))
2093             urzg(k,2)=scalar(uzgrad(1,k,1,i),erij(1))
2094             urzg(k,3)=scalar(uzgrad(1,k,2,i),erij(1))
2095             vryg(k,1)=scalar(erder(1,k),uy(1,j))
2096             vryg(k,2)=scalar(uygrad(1,k,1,j),erij(1))
2097             vryg(k,3)=scalar(uygrad(1,k,2,j),erij(1))
2098             vrzg(k,1)=scalar(erder(1,k),uz(1,j))
2099             vrzg(k,2)=scalar(uzgrad(1,k,1,j),erij(1))
2100             vrzg(k,3)=scalar(uzgrad(1,k,2,j),erij(1))
2101           enddo
2102 cd          do k=1,3
2103 cd            do l=1,3
2104 cd              uryg(k,l)=0.0d0
2105 cd              urzg(k,l)=0.0d0
2106 cd              vryg(k,l)=0.0d0
2107 cd              vrzg(k,l)=0.0d0
2108 cd            enddo
2109 cd          enddo
2110 C Compute radial contributions to the gradient
2111           facr=-3.0d0*rrmij
2112           a22der=a22*facr
2113           a23der=a23*facr
2114           a32der=a32*facr
2115           a33der=a33*facr
2116 cd          a22der=0.0d0
2117 cd          a23der=0.0d0
2118 cd          a32der=0.0d0
2119 cd          a33der=0.0d0
2120           agg(1,1)=a22der*xj
2121           agg(2,1)=a22der*yj
2122           agg(3,1)=a22der*zj
2123           agg(1,2)=a23der*xj
2124           agg(2,2)=a23der*yj
2125           agg(3,2)=a23der*zj
2126           agg(1,3)=a32der*xj
2127           agg(2,3)=a32der*yj
2128           agg(3,3)=a32der*zj
2129           agg(1,4)=a33der*xj
2130           agg(2,4)=a33der*yj
2131           agg(3,4)=a33der*zj
2132 C Add the contributions coming from er
2133           fac3=-3.0d0*fac
2134           do k=1,3
2135             agg(k,1)=agg(k,1)+fac3*(uryg(k,1)*vry+vryg(k,1)*ury)
2136             agg(k,2)=agg(k,2)+fac3*(uryg(k,1)*vrz+vrzg(k,1)*ury)
2137             agg(k,3)=agg(k,3)+fac3*(urzg(k,1)*vry+vryg(k,1)*urz)
2138             agg(k,4)=agg(k,4)+fac3*(urzg(k,1)*vrz+vrzg(k,1)*urz)
2139           enddo
2140           do k=1,3
2141 C Derivatives in DC(i)
2142             ghalf1=0.5d0*agg(k,1)
2143             ghalf2=0.5d0*agg(k,2)
2144             ghalf3=0.5d0*agg(k,3)
2145             ghalf4=0.5d0*agg(k,4)
2146             aggi(k,1)=fac*(scalar(uygrad(1,k,1,i),uy(1,j))
2147      &      -3.0d0*uryg(k,2)*vry)+ghalf1
2148             aggi(k,2)=fac*(scalar(uygrad(1,k,1,i),uz(1,j))
2149      &      -3.0d0*uryg(k,2)*vrz)+ghalf2
2150             aggi(k,3)=fac*(scalar(uzgrad(1,k,1,i),uy(1,j))
2151      &      -3.0d0*urzg(k,2)*vry)+ghalf3
2152             aggi(k,4)=fac*(scalar(uzgrad(1,k,1,i),uz(1,j))
2153      &      -3.0d0*urzg(k,2)*vrz)+ghalf4
2154 C Derivatives in DC(i+1)
2155             aggi1(k,1)=fac*(scalar(uygrad(1,k,2,i),uy(1,j))
2156      &      -3.0d0*uryg(k,3)*vry)+agg(k,1)
2157             aggi1(k,2)=fac*(scalar(uygrad(1,k,2,i),uz(1,j))
2158      &      -3.0d0*uryg(k,3)*vrz)+agg(k,2)
2159             aggi1(k,3)=fac*(scalar(uzgrad(1,k,2,i),uy(1,j))
2160      &      -3.0d0*urzg(k,3)*vry)+agg(k,3)
2161             aggi1(k,4)=fac*(scalar(uzgrad(1,k,2,i),uz(1,j))
2162      &      -3.0d0*urzg(k,3)*vrz)+agg(k,4)
2163 C Derivatives in DC(j)
2164             aggj(k,1)=fac*(scalar(uygrad(1,k,1,j),uy(1,i))
2165      &      -3.0d0*vryg(k,2)*ury)+ghalf1
2166             aggj(k,2)=fac*(scalar(uzgrad(1,k,1,j),uy(1,i))
2167      &      -3.0d0*vrzg(k,2)*ury)+ghalf2
2168             aggj(k,3)=fac*(scalar(uygrad(1,k,1,j),uz(1,i))
2169      &      -3.0d0*vryg(k,2)*urz)+ghalf3
2170             aggj(k,4)=fac*(scalar(uzgrad(1,k,1,j),uz(1,i))
2171      &      -3.0d0*vrzg(k,2)*urz)+ghalf4
2172 C Derivatives in DC(j+1) or DC(nres-1)
2173             aggj1(k,1)=fac*(scalar(uygrad(1,k,2,j),uy(1,i))
2174      &      -3.0d0*vryg(k,3)*ury)
2175             aggj1(k,2)=fac*(scalar(uzgrad(1,k,2,j),uy(1,i))
2176      &      -3.0d0*vrzg(k,3)*ury)
2177             aggj1(k,3)=fac*(scalar(uygrad(1,k,2,j),uz(1,i))
2178      &      -3.0d0*vryg(k,3)*urz)
2179             aggj1(k,4)=fac*(scalar(uzgrad(1,k,2,j),uz(1,i))
2180      &      -3.0d0*vrzg(k,3)*urz)
2181 cd            aggi(k,1)=ghalf1
2182 cd            aggi(k,2)=ghalf2
2183 cd            aggi(k,3)=ghalf3
2184 cd            aggi(k,4)=ghalf4
2185 C Derivatives in DC(i+1)
2186 cd            aggi1(k,1)=agg(k,1)
2187 cd            aggi1(k,2)=agg(k,2)
2188 cd            aggi1(k,3)=agg(k,3)
2189 cd            aggi1(k,4)=agg(k,4)
2190 C Derivatives in DC(j)
2191 cd            aggj(k,1)=ghalf1
2192 cd            aggj(k,2)=ghalf2
2193 cd            aggj(k,3)=ghalf3
2194 cd            aggj(k,4)=ghalf4
2195 C Derivatives in DC(j+1)
2196 cd            aggj1(k,1)=0.0d0
2197 cd            aggj1(k,2)=0.0d0
2198 cd            aggj1(k,3)=0.0d0
2199 cd            aggj1(k,4)=0.0d0
2200             if (j.eq.nres-1 .and. i.lt.j-2) then
2201               do l=1,4
2202                 aggj1(k,l)=aggj1(k,l)+agg(k,l)
2203 cd                aggj1(k,l)=agg(k,l)
2204               enddo
2205             endif
2206           enddo
2207           endif
2208 c          goto 11111
2209 C Check the loc-el terms by numerical integration
2210           acipa(1,1)=a22
2211           acipa(1,2)=a23
2212           acipa(2,1)=a32
2213           acipa(2,2)=a33
2214           a22=-a22
2215           a23=-a23
2216           do l=1,2
2217             do k=1,3
2218               agg(k,l)=-agg(k,l)
2219               aggi(k,l)=-aggi(k,l)
2220               aggi1(k,l)=-aggi1(k,l)
2221               aggj(k,l)=-aggj(k,l)
2222               aggj1(k,l)=-aggj1(k,l)
2223             enddo
2224           enddo
2225           if (j.lt.nres-1) then
2226             a22=-a22
2227             a32=-a32
2228             do l=1,3,2
2229               do k=1,3
2230                 agg(k,l)=-agg(k,l)
2231                 aggi(k,l)=-aggi(k,l)
2232                 aggi1(k,l)=-aggi1(k,l)
2233                 aggj(k,l)=-aggj(k,l)
2234                 aggj1(k,l)=-aggj1(k,l)
2235               enddo
2236             enddo
2237           else
2238             a22=-a22
2239             a23=-a23
2240             a32=-a32
2241             a33=-a33
2242             do l=1,4
2243               do k=1,3
2244                 agg(k,l)=-agg(k,l)
2245                 aggi(k,l)=-aggi(k,l)
2246                 aggi1(k,l)=-aggi1(k,l)
2247                 aggj(k,l)=-aggj(k,l)
2248                 aggj1(k,l)=-aggj1(k,l)
2249               enddo
2250             enddo
2251           endif
2252           ENDIF ! WCORR
2253 11111     continue
2254           IF (wel_loc.gt.0.0d0) THEN
2255 C Contribution to the local-electrostatic energy coming from the i-j pair
2256           eel_loc_ij=a22*muij(1)+a23*muij(2)+a32*muij(3)
2257      &     +a33*muij(4)
2258 cd          write (iout,*) 'i',i,' j',j,' eel_loc_ij',eel_loc_ij
2259 cd          write (iout,*) a22,muij(1),a23,muij(2),a32,muij(3)
2260           eel_loc=eel_loc+eel_loc_ij
2261 C Partial derivatives in virtual-bond dihedral angles gamma
2262           if (calc_grad) then
2263           if (i.gt.1)
2264      &    gel_loc_loc(i-1)=gel_loc_loc(i-1)+
2265      &            a22*muder(1,i)*mu(1,j)+a23*muder(1,i)*mu(2,j)
2266      &           +a32*muder(2,i)*mu(1,j)+a33*muder(2,i)*mu(2,j)
2267           gel_loc_loc(j-1)=gel_loc_loc(j-1)+
2268      &            a22*mu(1,i)*muder(1,j)+a23*mu(1,i)*muder(2,j)
2269      &           +a32*mu(2,i)*muder(1,j)+a33*mu(2,i)*muder(2,j)
2270 cd          call checkint3(i,j,mu1,mu2,a22,a23,a32,a33,acipa,eel_loc_ij)
2271 cd          write(iout,*) 'agg  ',agg
2272 cd          write(iout,*) 'aggi ',aggi
2273 cd          write(iout,*) 'aggi1',aggi1
2274 cd          write(iout,*) 'aggj ',aggj
2275 cd          write(iout,*) 'aggj1',aggj1
2276
2277 C Derivatives of eello in DC(i+1) thru DC(j-1) or DC(nres-2)
2278           do l=1,3
2279             ggg(l)=agg(l,1)*muij(1)+
2280      &          agg(l,2)*muij(2)+agg(l,3)*muij(3)+agg(l,4)*muij(4)
2281           enddo
2282           do k=i+2,j2
2283             do l=1,3
2284               gel_loc(l,k)=gel_loc(l,k)+ggg(l)
2285             enddo
2286           enddo
2287 C Remaining derivatives of eello
2288           do l=1,3
2289             gel_loc(l,i)=gel_loc(l,i)+aggi(l,1)*muij(1)+
2290      &          aggi(l,2)*muij(2)+aggi(l,3)*muij(3)+aggi(l,4)*muij(4)
2291             gel_loc(l,i+1)=gel_loc(l,i+1)+aggi1(l,1)*muij(1)+
2292      &          aggi1(l,2)*muij(2)+aggi1(l,3)*muij(3)+aggi1(l,4)*muij(4)
2293             gel_loc(l,j)=gel_loc(l,j)+aggj(l,1)*muij(1)+
2294      &          aggj(l,2)*muij(2)+aggj(l,3)*muij(3)+aggj(l,4)*muij(4)
2295             gel_loc(l,j1)=gel_loc(l,j1)+aggj1(l,1)*muij(1)+
2296      &          aggj1(l,2)*muij(2)+aggj1(l,3)*muij(3)+aggj1(l,4)*muij(4)
2297           enddo
2298           endif
2299           ENDIF
2300           if (wturn3.gt.0.0d0 .or. wturn4.gt.0.0d0) then
2301 C Contributions from turns
2302             a_temp(1,1)=a22
2303             a_temp(1,2)=a23
2304             a_temp(2,1)=a32
2305             a_temp(2,2)=a33
2306             call eturn34(i,j,eello_turn3,eello_turn4)
2307           endif
2308 C Change 12/26/95 to calculate four-body contributions to H-bonding energy
2309           if (j.gt.i+1 .and. num_conti.le.maxconts) then
2310 C
2311 C Calculate the contact function. The ith column of the array JCONT will
2312 C contain the numbers of atoms that make contacts with the atom I (of numbers
2313 C greater than I). The arrays FACONT and GACONT will contain the values of
2314 C the contact function and its derivative.
2315 c           r0ij=1.02D0*rpp(iteli,itelj)
2316 c           r0ij=1.11D0*rpp(iteli,itelj)
2317             r0ij=2.20D0*rpp(iteli,itelj)
2318 c           r0ij=1.55D0*rpp(iteli,itelj)
2319             call gcont(rij,r0ij,1.0D0,0.2d0*r0ij,fcont,fprimcont)
2320             if (fcont.gt.0.0D0) then
2321               num_conti=num_conti+1
2322               if (num_conti.gt.maxconts) then
2323                 write (iout,*) 'WARNING - max. # of contacts exceeded;',
2324      &                         ' will skip next contacts for this conf.'
2325               else
2326                 jcont_hb(num_conti,i)=j
2327                 IF (wcorr4.gt.0.0d0 .or. wcorr5.gt.0.0d0 .or.
2328      &          wcorr6.gt.0.0d0 .or. wturn6.gt.0.0d0) THEN
2329 C 9/30/99 (AL) - store components necessary to evaluate higher-order loc-el
2330 C  terms.
2331                 d_cont(num_conti,i)=rij
2332 cd                write (2,'(3e15.5)') rij,r0ij+0.2d0*r0ij,rij
2333 C     --- Electrostatic-interaction matrix ---
2334                 a_chuj(1,1,num_conti,i)=a22
2335                 a_chuj(1,2,num_conti,i)=a23
2336                 a_chuj(2,1,num_conti,i)=a32
2337                 a_chuj(2,2,num_conti,i)=a33
2338 C     --- Gradient of rij
2339                 do kkk=1,3
2340                   grij_hb_cont(kkk,num_conti,i)=erij(kkk)
2341                 enddo
2342 c             if (i.eq.1) then
2343 c                a_chuj(1,1,num_conti,i)=-0.61d0
2344 c                a_chuj(1,2,num_conti,i)= 0.4d0
2345 c                a_chuj(2,1,num_conti,i)= 0.65d0
2346 c                a_chuj(2,2,num_conti,i)= 0.50d0
2347 c             else if (i.eq.2) then
2348 c                a_chuj(1,1,num_conti,i)= 0.0d0
2349 c                a_chuj(1,2,num_conti,i)= 0.0d0
2350 c                a_chuj(2,1,num_conti,i)= 0.0d0
2351 c                a_chuj(2,2,num_conti,i)= 0.0d0
2352 c             endif
2353 C     --- and its gradients
2354 cd                write (iout,*) 'i',i,' j',j
2355 cd                do kkk=1,3
2356 cd                write (iout,*) 'iii 1 kkk',kkk
2357 cd                write (iout,*) agg(kkk,:)
2358 cd                enddo
2359 cd                do kkk=1,3
2360 cd                write (iout,*) 'iii 2 kkk',kkk
2361 cd                write (iout,*) aggi(kkk,:)
2362 cd                enddo
2363 cd                do kkk=1,3
2364 cd                write (iout,*) 'iii 3 kkk',kkk
2365 cd                write (iout,*) aggi1(kkk,:)
2366 cd                enddo
2367 cd                do kkk=1,3
2368 cd                write (iout,*) 'iii 4 kkk',kkk
2369 cd                write (iout,*) aggj(kkk,:)
2370 cd                enddo
2371 cd                do kkk=1,3
2372 cd                write (iout,*) 'iii 5 kkk',kkk
2373 cd                write (iout,*) aggj1(kkk,:)
2374 cd                enddo
2375                 kkll=0
2376                 do k=1,2
2377                   do l=1,2
2378                     kkll=kkll+1
2379                     do m=1,3
2380                       a_chuj_der(k,l,m,1,num_conti,i)=agg(m,kkll)
2381                       a_chuj_der(k,l,m,2,num_conti,i)=aggi(m,kkll)
2382                       a_chuj_der(k,l,m,3,num_conti,i)=aggi1(m,kkll)
2383                       a_chuj_der(k,l,m,4,num_conti,i)=aggj(m,kkll)
2384                       a_chuj_der(k,l,m,5,num_conti,i)=aggj1(m,kkll)
2385 c                      do mm=1,5
2386 c                      a_chuj_der(k,l,m,mm,num_conti,i)=0.0d0
2387 c                      enddo
2388                     enddo
2389                   enddo
2390                 enddo
2391                 ENDIF
2392                 IF (wcorr4.eq.0.0d0 .and. wcorr.gt.0.0d0) THEN
2393 C Calculate contact energies
2394                 cosa4=4.0D0*cosa
2395                 wij=cosa-3.0D0*cosb*cosg
2396                 cosbg1=cosb+cosg
2397                 cosbg2=cosb-cosg
2398 c               fac3=dsqrt(-ael6i)/r0ij**3
2399                 fac3=dsqrt(-ael6i)*r3ij
2400                 ees0pij=dsqrt(4.0D0+cosa4+wij*wij-3.0D0*cosbg1*cosbg1)
2401                 ees0mij=dsqrt(4.0D0-cosa4+wij*wij-3.0D0*cosbg2*cosbg2)
2402 c               ees0mij=0.0D0
2403                 ees0p(num_conti,i)=0.5D0*fac3*(ees0pij+ees0mij)
2404                 ees0m(num_conti,i)=0.5D0*fac3*(ees0pij-ees0mij)
2405 C Diagnostics. Comment out or remove after debugging!
2406 c               ees0p(num_conti,i)=0.5D0*fac3*ees0pij
2407 c               ees0m(num_conti,i)=0.5D0*fac3*ees0mij
2408 c               ees0m(num_conti,i)=0.0D0
2409 C End diagnostics.
2410 c                write (iout,*) 'i=',i,' j=',j,' rij=',rij,' r0ij=',r0ij,
2411 c     & ' ees0ij=',ees0p(num_conti,i),ees0m(num_conti,i),' fcont=',fcont
2412                 facont_hb(num_conti,i)=fcont
2413                 if (calc_grad) then
2414 C Angular derivatives of the contact function
2415                 ees0pij1=fac3/ees0pij
2416                 ees0mij1=fac3/ees0mij
2417                 fac3p=-3.0D0*fac3*rrmij
2418                 ees0pijp=0.5D0*fac3p*(ees0pij+ees0mij)
2419                 ees0mijp=0.5D0*fac3p*(ees0pij-ees0mij)
2420 c               ees0mij1=0.0D0
2421                 ecosa1=       ees0pij1*( 1.0D0+0.5D0*wij)
2422                 ecosb1=-1.5D0*ees0pij1*(wij*cosg+cosbg1)
2423                 ecosg1=-1.5D0*ees0pij1*(wij*cosb+cosbg1)
2424                 ecosa2=       ees0mij1*(-1.0D0+0.5D0*wij)
2425                 ecosb2=-1.5D0*ees0mij1*(wij*cosg+cosbg2)
2426                 ecosg2=-1.5D0*ees0mij1*(wij*cosb-cosbg2)
2427                 ecosap=ecosa1+ecosa2
2428                 ecosbp=ecosb1+ecosb2
2429                 ecosgp=ecosg1+ecosg2
2430                 ecosam=ecosa1-ecosa2
2431                 ecosbm=ecosb1-ecosb2
2432                 ecosgm=ecosg1-ecosg2
2433 C Diagnostics
2434 c               ecosap=ecosa1
2435 c               ecosbp=ecosb1
2436 c               ecosgp=ecosg1
2437 c               ecosam=0.0D0
2438 c               ecosbm=0.0D0
2439 c               ecosgm=0.0D0
2440 C End diagnostics
2441                 fprimcont=fprimcont/rij
2442 cd              facont_hb(num_conti,i)=1.0D0
2443 C Following line is for diagnostics.
2444 cd              fprimcont=0.0D0
2445                 do k=1,3
2446                   dcosb(k)=rmij*(dc_norm(k,i)-erij(k)*cosb)
2447                   dcosg(k)=rmij*(dc_norm(k,j)-erij(k)*cosg)
2448                 enddo
2449                 do k=1,3
2450                   gggp(k)=ecosbp*dcosb(k)+ecosgp*dcosg(k)
2451                   gggm(k)=ecosbm*dcosb(k)+ecosgm*dcosg(k)
2452                 enddo
2453                 gggp(1)=gggp(1)+ees0pijp*xj
2454                 gggp(2)=gggp(2)+ees0pijp*yj
2455                 gggp(3)=gggp(3)+ees0pijp*zj
2456                 gggm(1)=gggm(1)+ees0mijp*xj
2457                 gggm(2)=gggm(2)+ees0mijp*yj
2458                 gggm(3)=gggm(3)+ees0mijp*zj
2459 C Derivatives due to the contact function
2460                 gacont_hbr(1,num_conti,i)=fprimcont*xj
2461                 gacont_hbr(2,num_conti,i)=fprimcont*yj
2462                 gacont_hbr(3,num_conti,i)=fprimcont*zj
2463                 do k=1,3
2464                   ghalfp=0.5D0*gggp(k)
2465                   ghalfm=0.5D0*gggm(k)
2466                   gacontp_hb1(k,num_conti,i)=ghalfp
2467      &              +(ecosap*(dc_norm(k,j)-cosa*dc_norm(k,i))
2468      &              + ecosbp*(erij(k)-cosb*dc_norm(k,i)))*vbld_inv(i+1)
2469                   gacontp_hb2(k,num_conti,i)=ghalfp
2470      &              +(ecosap*(dc_norm(k,i)-cosa*dc_norm(k,j))
2471      &              + ecosgp*(erij(k)-cosg*dc_norm(k,j)))*vbld_inv(j+1)
2472                   gacontp_hb3(k,num_conti,i)=gggp(k)
2473                   gacontm_hb1(k,num_conti,i)=ghalfm
2474      &              +(ecosam*(dc_norm(k,j)-cosa*dc_norm(k,i))
2475      &              + ecosbm*(erij(k)-cosb*dc_norm(k,i)))*vbld_inv(i+1)
2476                   gacontm_hb2(k,num_conti,i)=ghalfm
2477      &              +(ecosam*(dc_norm(k,i)-cosa*dc_norm(k,j))
2478      &              + ecosgm*(erij(k)-cosg*dc_norm(k,j)))*vbld_inv(j+1)
2479                   gacontm_hb3(k,num_conti,i)=gggm(k)
2480                 enddo
2481                 endif
2482 C Diagnostics. Comment out or remove after debugging!
2483 cdiag           do k=1,3
2484 cdiag             gacontp_hb1(k,num_conti,i)=0.0D0
2485 cdiag             gacontp_hb2(k,num_conti,i)=0.0D0
2486 cdiag             gacontp_hb3(k,num_conti,i)=0.0D0
2487 cdiag             gacontm_hb1(k,num_conti,i)=0.0D0
2488 cdiag             gacontm_hb2(k,num_conti,i)=0.0D0
2489 cdiag             gacontm_hb3(k,num_conti,i)=0.0D0
2490 cdiag           enddo
2491               ENDIF ! wcorr
2492               endif  ! num_conti.le.maxconts
2493             endif  ! fcont.gt.0
2494           endif    ! j.gt.i+1
2495  1216     continue
2496         enddo ! j
2497         num_cont_hb(i)=num_conti
2498  1215   continue
2499       enddo   ! i
2500 cd      do i=1,nres
2501 cd        write (iout,'(i3,3f10.5,5x,3f10.5)')
2502 cd     &     i,(gel_loc(k,i),k=1,3),gel_loc_loc(i)
2503 cd      enddo
2504 c 12/7/99 Adam eello_turn3 will be considered as a separate energy term
2505 ccc      eel_loc=eel_loc+eello_turn3
2506       return
2507       end
2508 C-----------------------------------------------------------------------------
2509       subroutine eturn34(i,j,eello_turn3,eello_turn4)
2510 C Third- and fourth-order contributions from turns
2511       implicit real*8 (a-h,o-z)
2512       include 'DIMENSIONS'
2513       include 'DIMENSIONS.ZSCOPT'
2514       include 'COMMON.IOUNITS'
2515       include 'COMMON.GEO'
2516       include 'COMMON.VAR'
2517       include 'COMMON.LOCAL'
2518       include 'COMMON.CHAIN'
2519       include 'COMMON.DERIV'
2520       include 'COMMON.INTERACT'
2521       include 'COMMON.CONTACTS'
2522       include 'COMMON.TORSION'
2523       include 'COMMON.VECTORS'
2524       include 'COMMON.FFIELD'
2525       dimension ggg(3)
2526       double precision auxmat(2,2),auxmat1(2,2),auxmat2(2,2),pizda(2,2),
2527      &  e1t(2,2),e2t(2,2),e3t(2,2),e1tder(2,2),e2tder(2,2),e3tder(2,2),
2528      &  e1a(2,2),ae3(2,2),ae3e2(2,2),auxvec(2),auxvec1(2)
2529       double precision agg(3,4),aggi(3,4),aggi1(3,4),
2530      &    aggj(3,4),aggj1(3,4),a_temp(2,2)
2531       common /locel/ a_temp,agg,aggi,aggi1,aggj,aggj1,j1,j2
2532       if (j.eq.i+2) then
2533 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
2534 C
2535 C               Third-order contributions
2536 C
2537 C                 (i+2)o----(i+3)
2538 C                      | |
2539 C                      | |
2540 C                 (i+1)o----i
2541 C
2542 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
2543 cd        call checkint_turn3(i,a_temp,eello_turn3_num)
2544         call matmat2(EUg(1,1,i+1),EUg(1,1,i+2),auxmat(1,1))
2545         call transpose2(auxmat(1,1),auxmat1(1,1))
2546         call matmat2(a_temp(1,1),auxmat1(1,1),pizda(1,1))
2547         eello_turn3=eello_turn3+0.5d0*(pizda(1,1)+pizda(2,2))
2548 cd        write (2,*) 'i,',i,' j',j,'eello_turn3',
2549 cd     &    0.5d0*(pizda(1,1)+pizda(2,2)),
2550 cd     &    ' eello_turn3_num',4*eello_turn3_num
2551         if (calc_grad) then
2552 C Derivatives in gamma(i)
2553         call matmat2(EUgder(1,1,i+1),EUg(1,1,i+2),auxmat2(1,1))
2554         call transpose2(auxmat2(1,1),pizda(1,1))
2555         call matmat2(a_temp(1,1),pizda(1,1),pizda(1,1))
2556         gel_loc_turn3(i)=gel_loc_turn3(i)+0.5d0*(pizda(1,1)+pizda(2,2))
2557 C Derivatives in gamma(i+1)
2558         call matmat2(EUg(1,1,i+1),EUgder(1,1,i+2),auxmat2(1,1))
2559         call transpose2(auxmat2(1,1),pizda(1,1))
2560         call matmat2(a_temp(1,1),pizda(1,1),pizda(1,1))
2561         gel_loc_turn3(i+1)=gel_loc_turn3(i+1)
2562      &    +0.5d0*(pizda(1,1)+pizda(2,2))
2563 C Cartesian derivatives
2564         do l=1,3
2565           a_temp(1,1)=aggi(l,1)
2566           a_temp(1,2)=aggi(l,2)
2567           a_temp(2,1)=aggi(l,3)
2568           a_temp(2,2)=aggi(l,4)
2569           call matmat2(a_temp(1,1),auxmat1(1,1),pizda(1,1))
2570           gcorr3_turn(l,i)=gcorr3_turn(l,i)
2571      &      +0.5d0*(pizda(1,1)+pizda(2,2))
2572           a_temp(1,1)=aggi1(l,1)
2573           a_temp(1,2)=aggi1(l,2)
2574           a_temp(2,1)=aggi1(l,3)
2575           a_temp(2,2)=aggi1(l,4)
2576           call matmat2(a_temp(1,1),auxmat1(1,1),pizda(1,1))
2577           gcorr3_turn(l,i+1)=gcorr3_turn(l,i+1)
2578      &      +0.5d0*(pizda(1,1)+pizda(2,2))
2579           a_temp(1,1)=aggj(l,1)
2580           a_temp(1,2)=aggj(l,2)
2581           a_temp(2,1)=aggj(l,3)
2582           a_temp(2,2)=aggj(l,4)
2583           call matmat2(a_temp(1,1),auxmat1(1,1),pizda(1,1))
2584           gcorr3_turn(l,j)=gcorr3_turn(l,j)
2585      &      +0.5d0*(pizda(1,1)+pizda(2,2))
2586           a_temp(1,1)=aggj1(l,1)
2587           a_temp(1,2)=aggj1(l,2)
2588           a_temp(2,1)=aggj1(l,3)
2589           a_temp(2,2)=aggj1(l,4)
2590           call matmat2(a_temp(1,1),auxmat1(1,1),pizda(1,1))
2591           gcorr3_turn(l,j1)=gcorr3_turn(l,j1)
2592      &      +0.5d0*(pizda(1,1)+pizda(2,2))
2593         enddo
2594         endif
2595       else if (j.eq.i+3) then
2596 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
2597 C
2598 C               Fourth-order contributions
2599 C
2600 C                 (i+3)o----(i+4)
2601 C                     /  |
2602 C               (i+2)o   |
2603 C                     \  |
2604 C                 (i+1)o----i
2605 C
2606 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
2607 cd        call checkint_turn4(i,a_temp,eello_turn4_num)
2608         iti1=itortyp(itype(i+1))
2609         iti2=itortyp(itype(i+2))
2610         iti3=itortyp(itype(i+3))
2611         call transpose2(EUg(1,1,i+1),e1t(1,1))
2612         call transpose2(Eug(1,1,i+2),e2t(1,1))
2613         call transpose2(Eug(1,1,i+3),e3t(1,1))
2614         call matmat2(e1t(1,1),a_temp(1,1),e1a(1,1))
2615         call matvec2(e1a(1,1),Ub2(1,i+3),auxvec(1))
2616         s1=scalar2(b1(1,iti2),auxvec(1))
2617         call matmat2(a_temp(1,1),e3t(1,1),ae3(1,1))
2618         call matvec2(ae3(1,1),Ub2(1,i+2),auxvec(1))
2619         s2=scalar2(b1(1,iti1),auxvec(1))
2620         call matmat2(ae3(1,1),e2t(1,1),ae3e2(1,1))
2621         call matmat2(ae3e2(1,1),e1t(1,1),pizda(1,1))
2622         s3=0.5d0*(pizda(1,1)+pizda(2,2))
2623         eello_turn4=eello_turn4-(s1+s2+s3)
2624 cd        write (2,*) 'i,',i,' j',j,'eello_turn4',-(s1+s2+s3),
2625 cd     &    ' eello_turn4_num',8*eello_turn4_num
2626 C Derivatives in gamma(i)
2627         if (calc_grad) then
2628         call transpose2(EUgder(1,1,i+1),e1tder(1,1))
2629         call matmat2(e1tder(1,1),a_temp(1,1),auxmat(1,1))
2630         call matvec2(auxmat(1,1),Ub2(1,i+3),auxvec(1))
2631         s1=scalar2(b1(1,iti2),auxvec(1))
2632         call matmat2(ae3e2(1,1),e1tder(1,1),pizda(1,1))
2633         s3=0.5d0*(pizda(1,1)+pizda(2,2))
2634         gel_loc_turn4(i)=gel_loc_turn4(i)-(s1+s3)
2635 C Derivatives in gamma(i+1)
2636         call transpose2(EUgder(1,1,i+2),e2tder(1,1))
2637         call matvec2(ae3(1,1),Ub2der(1,i+2),auxvec(1))
2638         s2=scalar2(b1(1,iti1),auxvec(1))
2639         call matmat2(ae3(1,1),e2tder(1,1),auxmat(1,1))
2640         call matmat2(auxmat(1,1),e1t(1,1),pizda(1,1))
2641         s3=0.5d0*(pizda(1,1)+pizda(2,2))
2642         gel_loc_turn4(i+1)=gel_loc_turn4(i+1)-(s2+s3)
2643 C Derivatives in gamma(i+2)
2644         call transpose2(EUgder(1,1,i+3),e3tder(1,1))
2645         call matvec2(e1a(1,1),Ub2der(1,i+3),auxvec(1))
2646         s1=scalar2(b1(1,iti2),auxvec(1))
2647         call matmat2(a_temp(1,1),e3tder(1,1),auxmat(1,1))
2648         call matvec2(auxmat(1,1),Ub2(1,i+2),auxvec(1))
2649         s2=scalar2(b1(1,iti1),auxvec(1))
2650         call matmat2(auxmat(1,1),e2t(1,1),auxmat(1,1))
2651         call matmat2(auxmat(1,1),e1t(1,1),pizda(1,1))
2652         s3=0.5d0*(pizda(1,1)+pizda(2,2))
2653         gel_loc_turn4(i+2)=gel_loc_turn4(i+2)-(s1+s2+s3)
2654 C Cartesian derivatives
2655 C Derivatives of this turn contributions in DC(i+2)
2656         if (j.lt.nres-1) then
2657           do l=1,3
2658             a_temp(1,1)=agg(l,1)
2659             a_temp(1,2)=agg(l,2)
2660             a_temp(2,1)=agg(l,3)
2661             a_temp(2,2)=agg(l,4)
2662             call matmat2(e1t(1,1),a_temp(1,1),e1a(1,1))
2663             call matvec2(e1a(1,1),Ub2(1,i+3),auxvec(1))
2664             s1=scalar2(b1(1,iti2),auxvec(1))
2665             call matmat2(a_temp(1,1),e3t(1,1),ae3(1,1))
2666             call matvec2(ae3(1,1),Ub2(1,i+2),auxvec(1))
2667             s2=scalar2(b1(1,iti1),auxvec(1))
2668             call matmat2(ae3(1,1),e2t(1,1),ae3e2(1,1))
2669             call matmat2(ae3e2(1,1),e1t(1,1),pizda(1,1))
2670             s3=0.5d0*(pizda(1,1)+pizda(2,2))
2671             ggg(l)=-(s1+s2+s3)
2672             gcorr4_turn(l,i+2)=gcorr4_turn(l,i+2)-(s1+s2+s3)
2673           enddo
2674         endif
2675 C Remaining derivatives of this turn contribution
2676         do l=1,3
2677           a_temp(1,1)=aggi(l,1)
2678           a_temp(1,2)=aggi(l,2)
2679           a_temp(2,1)=aggi(l,3)
2680           a_temp(2,2)=aggi(l,4)
2681           call matmat2(e1t(1,1),a_temp(1,1),e1a(1,1))
2682           call matvec2(e1a(1,1),Ub2(1,i+3),auxvec(1))
2683           s1=scalar2(b1(1,iti2),auxvec(1))
2684           call matmat2(a_temp(1,1),e3t(1,1),ae3(1,1))
2685           call matvec2(ae3(1,1),Ub2(1,i+2),auxvec(1))
2686           s2=scalar2(b1(1,iti1),auxvec(1))
2687           call matmat2(ae3(1,1),e2t(1,1),ae3e2(1,1))
2688           call matmat2(ae3e2(1,1),e1t(1,1),pizda(1,1))
2689           s3=0.5d0*(pizda(1,1)+pizda(2,2))
2690           gcorr4_turn(l,i)=gcorr4_turn(l,i)-(s1+s2+s3)
2691           a_temp(1,1)=aggi1(l,1)
2692           a_temp(1,2)=aggi1(l,2)
2693           a_temp(2,1)=aggi1(l,3)
2694           a_temp(2,2)=aggi1(l,4)
2695           call matmat2(e1t(1,1),a_temp(1,1),e1a(1,1))
2696           call matvec2(e1a(1,1),Ub2(1,i+3),auxvec(1))
2697           s1=scalar2(b1(1,iti2),auxvec(1))
2698           call matmat2(a_temp(1,1),e3t(1,1),ae3(1,1))
2699           call matvec2(ae3(1,1),Ub2(1,i+2),auxvec(1))
2700           s2=scalar2(b1(1,iti1),auxvec(1))
2701           call matmat2(ae3(1,1),e2t(1,1),ae3e2(1,1))
2702           call matmat2(ae3e2(1,1),e1t(1,1),pizda(1,1))
2703           s3=0.5d0*(pizda(1,1)+pizda(2,2))
2704           gcorr4_turn(l,i+1)=gcorr4_turn(l,i+1)-(s1+s2+s3)
2705           a_temp(1,1)=aggj(l,1)
2706           a_temp(1,2)=aggj(l,2)
2707           a_temp(2,1)=aggj(l,3)
2708           a_temp(2,2)=aggj(l,4)
2709           call matmat2(e1t(1,1),a_temp(1,1),e1a(1,1))
2710           call matvec2(e1a(1,1),Ub2(1,i+3),auxvec(1))
2711           s1=scalar2(b1(1,iti2),auxvec(1))
2712           call matmat2(a_temp(1,1),e3t(1,1),ae3(1,1))
2713           call matvec2(ae3(1,1),Ub2(1,i+2),auxvec(1))
2714           s2=scalar2(b1(1,iti1),auxvec(1))
2715           call matmat2(ae3(1,1),e2t(1,1),ae3e2(1,1))
2716           call matmat2(ae3e2(1,1),e1t(1,1),pizda(1,1))
2717           s3=0.5d0*(pizda(1,1)+pizda(2,2))
2718           gcorr4_turn(l,j)=gcorr4_turn(l,j)-(s1+s2+s3)
2719           a_temp(1,1)=aggj1(l,1)
2720           a_temp(1,2)=aggj1(l,2)
2721           a_temp(2,1)=aggj1(l,3)
2722           a_temp(2,2)=aggj1(l,4)
2723           call matmat2(e1t(1,1),a_temp(1,1),e1a(1,1))
2724           call matvec2(e1a(1,1),Ub2(1,i+3),auxvec(1))
2725           s1=scalar2(b1(1,iti2),auxvec(1))
2726           call matmat2(a_temp(1,1),e3t(1,1),ae3(1,1))
2727           call matvec2(ae3(1,1),Ub2(1,i+2),auxvec(1))
2728           s2=scalar2(b1(1,iti1),auxvec(1))
2729           call matmat2(ae3(1,1),e2t(1,1),ae3e2(1,1))
2730           call matmat2(ae3e2(1,1),e1t(1,1),pizda(1,1))
2731           s3=0.5d0*(pizda(1,1)+pizda(2,2))
2732           gcorr4_turn(l,j1)=gcorr4_turn(l,j1)-(s1+s2+s3)
2733         enddo
2734         endif
2735       endif
2736       return
2737       end
2738 C-----------------------------------------------------------------------------
2739       subroutine vecpr(u,v,w)
2740       implicit real*8(a-h,o-z)
2741       dimension u(3),v(3),w(3)
2742       w(1)=u(2)*v(3)-u(3)*v(2)
2743       w(2)=-u(1)*v(3)+u(3)*v(1)
2744       w(3)=u(1)*v(2)-u(2)*v(1)
2745       return
2746       end
2747 C-----------------------------------------------------------------------------
2748       subroutine unormderiv(u,ugrad,unorm,ungrad)
2749 C This subroutine computes the derivatives of a normalized vector u, given
2750 C the derivatives computed without normalization conditions, ugrad. Returns
2751 C ungrad.
2752       implicit none
2753       double precision u(3),ugrad(3,3),unorm,ungrad(3,3)
2754       double precision vec(3)
2755       double precision scalar
2756       integer i,j
2757 c      write (2,*) 'ugrad',ugrad
2758 c      write (2,*) 'u',u
2759       do i=1,3
2760         vec(i)=scalar(ugrad(1,i),u(1))
2761       enddo
2762 c      write (2,*) 'vec',vec
2763       do i=1,3
2764         do j=1,3
2765           ungrad(j,i)=(ugrad(j,i)-u(j)*vec(i))*unorm
2766         enddo
2767       enddo
2768 c      write (2,*) 'ungrad',ungrad
2769       return
2770       end
2771 C-----------------------------------------------------------------------------
2772       subroutine escp(evdw2,evdw2_14)
2773 C
2774 C This subroutine calculates the excluded-volume interaction energy between
2775 C peptide-group centers and side chains and its gradient in virtual-bond and
2776 C side-chain vectors.
2777 C
2778       implicit real*8 (a-h,o-z)
2779       include 'DIMENSIONS'
2780       include 'DIMENSIONS.ZSCOPT'
2781       include 'COMMON.GEO'
2782       include 'COMMON.VAR'
2783       include 'COMMON.LOCAL'
2784       include 'COMMON.CHAIN'
2785       include 'COMMON.DERIV'
2786       include 'COMMON.INTERACT'
2787       include 'COMMON.FFIELD'
2788       include 'COMMON.IOUNITS'
2789       dimension ggg(3)
2790       evdw2=0.0D0
2791       evdw2_14=0.0d0
2792 cd    print '(a)','Enter ESCP'
2793 c      write (iout,*) 'iatscp_s=',iatscp_s,' iatscp_e=',iatscp_e,
2794 c     &  ' scal14',scal14
2795       do i=iatscp_s,iatscp_e
2796         iteli=itel(i)
2797 c        write (iout,*) "i",i," iteli",iteli," nscp_gr",nscp_gr(i),
2798 c     &   " iscp",(iscpstart(i,j),iscpend(i,j),j=1,nscp_gr(i))
2799         if (iteli.eq.0) goto 1225
2800         xi=0.5D0*(c(1,i)+c(1,i+1))
2801         yi=0.5D0*(c(2,i)+c(2,i+1))
2802         zi=0.5D0*(c(3,i)+c(3,i+1))
2803
2804         do iint=1,nscp_gr(i)
2805
2806         do j=iscpstart(i,iint),iscpend(i,iint)
2807           itypj=itype(j)
2808 C Uncomment following three lines for SC-p interactions
2809 c         xj=c(1,nres+j)-xi
2810 c         yj=c(2,nres+j)-yi
2811 c         zj=c(3,nres+j)-zi
2812 C Uncomment following three lines for Ca-p interactions
2813           xj=c(1,j)-xi
2814           yj=c(2,j)-yi
2815           zj=c(3,j)-zi
2816           rrij=1.0D0/(xj*xj+yj*yj+zj*zj)
2817           fac=rrij**expon2
2818           e1=fac*fac*aad(itypj,iteli)
2819           e2=fac*bad(itypj,iteli)
2820           if (iabs(j-i) .le. 2) then
2821             e1=scal14*e1
2822             e2=scal14*e2
2823             evdw2_14=evdw2_14+e1+e2
2824           endif
2825           evdwij=e1+e2
2826 c          write (iout,*) i,j,evdwij
2827           evdw2=evdw2+evdwij
2828           if (calc_grad) then
2829 C
2830 C Calculate contributions to the gradient in the virtual-bond and SC vectors.
2831 C
2832           fac=-(evdwij+e1)*rrij
2833           ggg(1)=xj*fac
2834           ggg(2)=yj*fac
2835           ggg(3)=zj*fac
2836           if (j.lt.i) then
2837 cd          write (iout,*) 'j<i'
2838 C Uncomment following three lines for SC-p interactions
2839 c           do k=1,3
2840 c             gradx_scp(k,j)=gradx_scp(k,j)+ggg(k)
2841 c           enddo
2842           else
2843 cd          write (iout,*) 'j>i'
2844             do k=1,3
2845               ggg(k)=-ggg(k)
2846 C Uncomment following line for SC-p interactions
2847 c             gradx_scp(k,j)=gradx_scp(k,j)-ggg(k)
2848             enddo
2849           endif
2850           do k=1,3
2851             gvdwc_scp(k,i)=gvdwc_scp(k,i)-0.5D0*ggg(k)
2852           enddo
2853           kstart=min0(i+1,j)
2854           kend=max0(i-1,j-1)
2855 cd        write (iout,*) 'i=',i,' j=',j,' kstart=',kstart,' kend=',kend
2856 cd        write (iout,*) ggg(1),ggg(2),ggg(3)
2857           do k=kstart,kend
2858             do l=1,3
2859               gvdwc_scp(l,k)=gvdwc_scp(l,k)-ggg(l)
2860             enddo
2861           enddo
2862           endif
2863         enddo
2864         enddo ! iint
2865  1225   continue
2866       enddo ! i
2867       do i=1,nct
2868         do j=1,3
2869           gvdwc_scp(j,i)=expon*gvdwc_scp(j,i)
2870           gradx_scp(j,i)=expon*gradx_scp(j,i)
2871         enddo
2872       enddo
2873 C******************************************************************************
2874 C
2875 C                              N O T E !!!
2876 C
2877 C To save time the factor EXPON has been extracted from ALL components
2878 C of GVDWC and GRADX. Remember to multiply them by this factor before further
2879 C use!
2880 C
2881 C******************************************************************************
2882       return
2883       end
2884 C--------------------------------------------------------------------------
2885       subroutine edis(ehpb)
2886 C
2887 C Evaluate bridge-strain energy and its gradient in virtual-bond and SC vectors.
2888 C
2889       implicit real*8 (a-h,o-z)
2890       include 'DIMENSIONS'
2891       include 'COMMON.SBRIDGE'
2892       include 'COMMON.CHAIN'
2893       include 'COMMON.DERIV'
2894       include 'COMMON.VAR'
2895       include 'COMMON.INTERACT'
2896       include 'COMMON.IOUNITS'
2897       dimension ggg(3)
2898       ehpb=0.0D0
2899 cd      write(iout,*)'edis: nhpb=',nhpb,' fbr=',fbr
2900 cd      write(iout,*)'link_start=',link_start,' link_end=',link_end
2901       if (link_end.eq.0) return
2902       do i=link_start,link_end
2903 C If ihpb(i) and jhpb(i) > NRES, this is a SC-SC distance, otherwise a
2904 C CA-CA distance used in regularization of structure.
2905         ii=ihpb(i)
2906         jj=jhpb(i)
2907 C iii and jjj point to the residues for which the distance is assigned.
2908         if (ii.gt.nres) then
2909           iii=ii-nres
2910           jjj=jj-nres
2911         else
2912           iii=ii
2913           jjj=jj
2914         endif
2915 c        write (iout,*) "i",i," ii",ii," iii",iii," jj",jj," jjj",jjj,
2916 c     &    dhpb(i),dhpb1(i),forcon(i)
2917 C 24/11/03 AL: SS bridges handled separately because of introducing a specific
2918 C    distance and angle dependent SS bond potential.
2919         if (.not.dyn_ss .and. i.le.nss) then
2920 C 15/02/13 CC dynamic SSbond - additional check
2921         if (ii.gt.nres .and. itype(iii).eq.1 .and. itype(jjj).eq.1) then
2922           call ssbond_ene(iii,jjj,eij)
2923           ehpb=ehpb+2*eij
2924          endif
2925 cd          write (iout,*) "eij",eij
2926         else if (ii.gt.nres .and. jj.gt.nres) then
2927 c Restraints from contact prediction
2928           dd=dist(ii,jj)
2929           if (dhpb1(i).gt.0.0d0) then
2930             ehpb=ehpb+2*forcon(i)*gnmr1(dd,dhpb(i),dhpb1(i))
2931             fac=forcon(i)*gnmr1prim(dd,dhpb(i),dhpb1(i))/dd
2932 c            write (iout,*) "beta nmr",
2933 c     &        dd,2*forcon(i)*gnmr1(dd,dhpb(i),dhpb1(i))
2934           else
2935             dd=dist(ii,jj)
2936             rdis=dd-dhpb(i)
2937 C Get the force constant corresponding to this distance.
2938             waga=forcon(i)
2939 C Calculate the contribution to energy.
2940             ehpb=ehpb+waga*rdis*rdis
2941 c            write (iout,*) "beta reg",dd,waga*rdis*rdis
2942 C
2943 C Evaluate gradient.
2944 C
2945             fac=waga*rdis/dd
2946           endif
2947           do j=1,3
2948             ggg(j)=fac*(c(j,jj)-c(j,ii))
2949           enddo
2950           do j=1,3
2951             ghpbx(j,iii)=ghpbx(j,iii)-ggg(j)
2952             ghpbx(j,jjj)=ghpbx(j,jjj)+ggg(j)
2953           enddo
2954           do k=1,3
2955             ghpbc(k,jjj)=ghpbc(k,jjj)+ggg(k)
2956             ghpbc(k,iii)=ghpbc(k,iii)-ggg(k)
2957           enddo
2958         else
2959 C Calculate the distance between the two points and its difference from the
2960 C target distance.
2961           dd=dist(ii,jj)
2962           if (dhpb1(i).gt.0.0d0) then
2963             ehpb=ehpb+2*forcon(i)*gnmr1(dd,dhpb(i),dhpb1(i))
2964             fac=forcon(i)*gnmr1prim(dd,dhpb(i),dhpb1(i))/dd
2965 c            write (iout,*) "alph nmr",
2966 c     &        dd,2*forcon(i)*gnmr1(dd,dhpb(i),dhpb1(i))
2967           else
2968             rdis=dd-dhpb(i)
2969 C Get the force constant corresponding to this distance.
2970             waga=forcon(i)
2971 C Calculate the contribution to energy.
2972             ehpb=ehpb+waga*rdis*rdis
2973 c            write (iout,*) "alpha reg",dd,waga*rdis*rdis
2974 C
2975 C Evaluate gradient.
2976 C
2977             fac=waga*rdis/dd
2978           endif
2979 cd      print *,'i=',i,' ii=',ii,' jj=',jj,' dhpb=',dhpb(i),' dd=',dd,
2980 cd   &   ' waga=',waga,' fac=',fac
2981             do j=1,3
2982               ggg(j)=fac*(c(j,jj)-c(j,ii))
2983             enddo
2984 cd      print '(i3,3(1pe14.5))',i,(ggg(j),j=1,3)
2985 C If this is a SC-SC distance, we need to calculate the contributions to the
2986 C Cartesian gradient in the SC vectors (ghpbx).
2987           if (iii.lt.ii) then
2988           do j=1,3
2989             ghpbx(j,iii)=ghpbx(j,iii)-ggg(j)
2990             ghpbx(j,jjj)=ghpbx(j,jjj)+ggg(j)
2991           enddo
2992           endif
2993           do k=1,3
2994             ghpbc(k,jjj)=ghpbc(k,jjj)+ggg(k)
2995             ghpbc(k,iii)=ghpbc(k,iii)-ggg(k)
2996           enddo
2997         endif
2998       enddo
2999       ehpb=0.5D0*ehpb
3000       return
3001       end
3002 C--------------------------------------------------------------------------
3003       subroutine ssbond_ene(i,j,eij)
3004 C
3005 C Calculate the distance and angle dependent SS-bond potential energy
3006 C using a free-energy function derived based on RHF/6-31G** ab initio
3007 C calculations of diethyl disulfide.
3008 C
3009 C A. Liwo and U. Kozlowska, 11/24/03
3010 C
3011       implicit real*8 (a-h,o-z)
3012       include 'DIMENSIONS'
3013       include 'DIMENSIONS.ZSCOPT'
3014       include 'COMMON.SBRIDGE'
3015       include 'COMMON.CHAIN'
3016       include 'COMMON.DERIV'
3017       include 'COMMON.LOCAL'
3018       include 'COMMON.INTERACT'
3019       include 'COMMON.VAR'
3020       include 'COMMON.IOUNITS'
3021       double precision erij(3),dcosom1(3),dcosom2(3),gg(3)
3022       itypi=itype(i)
3023       xi=c(1,nres+i)
3024       yi=c(2,nres+i)
3025       zi=c(3,nres+i)
3026       dxi=dc_norm(1,nres+i)
3027       dyi=dc_norm(2,nres+i)
3028       dzi=dc_norm(3,nres+i)
3029       dsci_inv=dsc_inv(itypi)
3030       itypj=itype(j)
3031       dscj_inv=dsc_inv(itypj)
3032       xj=c(1,nres+j)-xi
3033       yj=c(2,nres+j)-yi
3034       zj=c(3,nres+j)-zi
3035       dxj=dc_norm(1,nres+j)
3036       dyj=dc_norm(2,nres+j)
3037       dzj=dc_norm(3,nres+j)
3038       rrij=1.0D0/(xj*xj+yj*yj+zj*zj)
3039       rij=dsqrt(rrij)
3040       erij(1)=xj*rij
3041       erij(2)=yj*rij
3042       erij(3)=zj*rij
3043       om1=dxi*erij(1)+dyi*erij(2)+dzi*erij(3)
3044       om2=dxj*erij(1)+dyj*erij(2)+dzj*erij(3)
3045       om12=dxi*dxj+dyi*dyj+dzi*dzj
3046       do k=1,3
3047         dcosom1(k)=rij*(dc_norm(k,nres+i)-om1*erij(k))
3048         dcosom2(k)=rij*(dc_norm(k,nres+j)-om2*erij(k))
3049       enddo
3050       rij=1.0d0/rij
3051       deltad=rij-d0cm
3052       deltat1=1.0d0-om1
3053       deltat2=1.0d0+om2
3054       deltat12=om2-om1+2.0d0
3055       cosphi=om12-om1*om2
3056       eij=akcm*deltad*deltad+akth*(deltat1*deltat1+deltat2*deltat2)
3057      &  +akct*deltad*deltat12+ebr
3058 c     &  +akct*deltad*deltat12
3059      &  +v1ss*cosphi+v2ss*cosphi*cosphi+v3ss*cosphi*cosphi*cosphi
3060       write(iout,*) i,j,"rij",rij,"d0cm",d0cm," akcm",akcm," akth",akth,
3061      &  " akct",akct," deltad",deltad," deltat",deltat1,deltat2,
3062      &  " deltat12",deltat12," eij",eij,"ebr",ebr
3063       ed=2*akcm*deltad+akct*deltat12
3064       pom1=akct*deltad
3065       pom2=v1ss+2*v2ss*cosphi+3*v3ss*cosphi*cosphi
3066       eom1=-2*akth*deltat1-pom1-om2*pom2
3067       eom2= 2*akth*deltat2+pom1-om1*pom2
3068       eom12=pom2
3069       do k=1,3
3070         gg(k)=ed*erij(k)+eom1*dcosom1(k)+eom2*dcosom2(k)
3071       enddo
3072       do k=1,3
3073         ghpbx(k,i)=ghpbx(k,i)-gg(k)
3074      &            +(eom12*dc_norm(k,nres+j)+eom1*erij(k))*dsci_inv
3075         ghpbx(k,j)=ghpbx(k,j)+gg(k)
3076      &            +(eom12*dc_norm(k,nres+i)+eom2*erij(k))*dscj_inv
3077       enddo
3078 C
3079 C Calculate the components of the gradient in DC and X
3080 C
3081       do k=i,j-1
3082         do l=1,3
3083           ghpbc(l,k)=ghpbc(l,k)+gg(l)
3084         enddo
3085       enddo
3086       return
3087       end
3088 C--------------------------------------------------------------------------
3089       subroutine ebond(estr)
3090 c
3091 c Evaluate the energy of stretching of the CA-CA and CA-SC virtual bonds
3092 c
3093       implicit real*8 (a-h,o-z)
3094       include 'DIMENSIONS'
3095       include 'DIMENSIONS.ZSCOPT'
3096       include 'COMMON.LOCAL'
3097       include 'COMMON.GEO'
3098       include 'COMMON.INTERACT'
3099       include 'COMMON.DERIV'
3100       include 'COMMON.VAR'
3101       include 'COMMON.CHAIN'
3102       include 'COMMON.IOUNITS'
3103       include 'COMMON.NAMES'
3104       include 'COMMON.FFIELD'
3105       include 'COMMON.CONTROL'
3106       double precision u(3),ud(3)
3107       logical :: lprn=.false.
3108       estr=0.0d0
3109       do i=nnt+1,nct
3110         diff = vbld(i)-vbldp0
3111 c        write (iout,*) i,vbld(i),vbldp0,diff,AKP*diff*diff
3112         estr=estr+diff*diff
3113         do j=1,3
3114           gradb(j,i-1)=AKP*diff*dc(j,i-1)/vbld(i)
3115         enddo
3116       enddo
3117       estr=0.5d0*AKP*estr
3118 c
3119 c 09/18/07 AL: multimodal bond potential based on AM1 CA-SC PMF's included
3120 c
3121       do i=nnt,nct
3122         iti=itype(i)
3123         if (iti.ne.10) then
3124           nbi=nbondterm(iti)
3125           if (nbi.eq.1) then
3126             diff=vbld(i+nres)-vbldsc0(1,iti)
3127             if (lprn)
3128      &      write (iout,*) i,iti,vbld(i+nres),vbldsc0(1,iti),diff,
3129      &      AKSC(1,iti),AKSC(1,iti)*diff*diff
3130             estr=estr+0.5d0*AKSC(1,iti)*diff*diff
3131             do j=1,3
3132               gradbx(j,i)=AKSC(1,iti)*diff*dc(j,i+nres)/vbld(i+nres)
3133             enddo
3134           else
3135             do j=1,nbi
3136               diff=vbld(i+nres)-vbldsc0(j,iti)
3137               ud(j)=aksc(j,iti)*diff
3138               u(j)=abond0(j,iti)+0.5d0*ud(j)*diff
3139             enddo
3140             uprod=u(1)
3141             do j=2,nbi
3142               uprod=uprod*u(j)
3143             enddo
3144             usum=0.0d0
3145             usumsqder=0.0d0
3146             do j=1,nbi
3147               uprod1=1.0d0
3148               uprod2=1.0d0
3149               do k=1,nbi
3150                 if (k.ne.j) then
3151                   uprod1=uprod1*u(k)
3152                   uprod2=uprod2*u(k)*u(k)
3153                 endif
3154               enddo
3155               usum=usum+uprod1
3156               usumsqder=usumsqder+ud(j)*uprod2
3157             enddo
3158             if (lprn)
3159      &      write (iout,*) i,iti,vbld(i+nres),(vbldsc0(j,iti),
3160      &      AKSC(j,iti),abond0(j,iti),u(j),j=1,nbi)
3161             estr=estr+uprod/usum
3162             do j=1,3
3163              gradbx(j,i)=usumsqder/(usum*usum)*dc(j,i+nres)/vbld(i+nres)
3164             enddo
3165           endif
3166         endif
3167       enddo
3168       return
3169       end
3170 #ifdef CRYST_THETA
3171 C--------------------------------------------------------------------------
3172       subroutine ebend(etheta)
3173 C
3174 C Evaluate the virtual-bond-angle energy given the virtual-bond dihedral
3175 C angles gamma and its derivatives in consecutive thetas and gammas.
3176 C
3177       implicit real*8 (a-h,o-z)
3178       include 'DIMENSIONS'
3179       include 'DIMENSIONS.ZSCOPT'
3180       include 'COMMON.LOCAL'
3181       include 'COMMON.GEO'
3182       include 'COMMON.INTERACT'
3183       include 'COMMON.DERIV'
3184       include 'COMMON.VAR'
3185       include 'COMMON.CHAIN'
3186       include 'COMMON.IOUNITS'
3187       include 'COMMON.NAMES'
3188       include 'COMMON.FFIELD'
3189       common /calcthet/ term1,term2,termm,diffak,ratak,
3190      & ak,aktc,termpre,termexp,sigc,sig0i,time11,time12,sigcsq,
3191      & delthe0,sig0inv,sigtc,sigsqtc,delthec,it
3192       double precision y(2),z(2)
3193       delta=0.02d0*pi
3194       time11=dexp(-2*time)
3195       time12=1.0d0
3196       etheta=0.0D0
3197 c      write (iout,*) "nres",nres
3198 c     write (*,'(a,i2)') 'EBEND ICG=',icg
3199 c      write (iout,*) ithet_start,ithet_end
3200       do i=ithet_start,ithet_end
3201 C Zero the energy function and its derivative at 0 or pi.
3202         call splinthet(theta(i),0.5d0*delta,ss,ssd)
3203         it=itype(i-1)
3204 c        if (i.gt.ithet_start .and.
3205 c     &     (itel(i-1).eq.0 .or. itel(i-2).eq.0)) goto 1215
3206 c        if (i.gt.3 .and. (i.le.4 .or. itel(i-3).ne.0)) then
3207 c          phii=phi(i)
3208 c          y(1)=dcos(phii)
3209 c          y(2)=dsin(phii)
3210 c        else
3211 c          y(1)=0.0D0
3212 c          y(2)=0.0D0
3213 c        endif
3214 c        if (i.lt.nres .and. itel(i).ne.0) then
3215 c          phii1=phi(i+1)
3216 c          z(1)=dcos(phii1)
3217 c          z(2)=dsin(phii1)
3218 c        else
3219 c          z(1)=0.0D0
3220 c          z(2)=0.0D0
3221 c        endif
3222         if (i.gt.3) then
3223 #ifdef OSF
3224           phii=phi(i)
3225           icrc=0
3226           call proc_proc(phii,icrc)
3227           if (icrc.eq.1) phii=150.0
3228 #else
3229           phii=phi(i)
3230 #endif
3231           y(1)=dcos(phii)
3232           y(2)=dsin(phii)
3233         else
3234           y(1)=0.0D0
3235           y(2)=0.0D0
3236         endif
3237         if (i.lt.nres) then
3238 #ifdef OSF
3239           phii1=phi(i+1)
3240           icrc=0
3241           call proc_proc(phii1,icrc)
3242           if (icrc.eq.1) phii1=150.0
3243           phii1=pinorm(phii1)
3244           z(1)=cos(phii1)
3245 #else
3246           phii1=phi(i+1)
3247           z(1)=dcos(phii1)
3248 #endif
3249           z(2)=dsin(phii1)
3250         else
3251           z(1)=0.0D0
3252           z(2)=0.0D0
3253         endif
3254 C Calculate the "mean" value of theta from the part of the distribution
3255 C dependent on the adjacent virtual-bond-valence angles (gamma1 & gamma2).
3256 C In following comments this theta will be referred to as t_c.
3257         thet_pred_mean=0.0d0
3258         do k=1,2
3259           athetk=athet(k,it)
3260           bthetk=bthet(k,it)
3261           thet_pred_mean=thet_pred_mean+athetk*y(k)+bthetk*z(k)
3262         enddo
3263 c        write (iout,*) "thet_pred_mean",thet_pred_mean
3264         dthett=thet_pred_mean*ssd
3265         thet_pred_mean=thet_pred_mean*ss+a0thet(it)
3266 c        write (iout,*) "thet_pred_mean",thet_pred_mean
3267 C Derivatives of the "mean" values in gamma1 and gamma2.
3268         dthetg1=(-athet(1,it)*y(2)+athet(2,it)*y(1))*ss
3269         dthetg2=(-bthet(1,it)*z(2)+bthet(2,it)*z(1))*ss
3270         if (theta(i).gt.pi-delta) then
3271           call theteng(pi-delta,thet_pred_mean,theta0(it),f0,fprim0,
3272      &         E_tc0)
3273           call mixder(pi-delta,thet_pred_mean,theta0(it),fprim_tc0)
3274           call theteng(pi,thet_pred_mean,theta0(it),f1,fprim1,E_tc1)
3275           call spline1(theta(i),pi-delta,delta,f0,f1,fprim0,ethetai,
3276      &        E_theta)
3277           call spline2(theta(i),pi-delta,delta,E_tc0,E_tc1,fprim_tc0,
3278      &        E_tc)
3279         else if (theta(i).lt.delta) then
3280           call theteng(delta,thet_pred_mean,theta0(it),f0,fprim0,E_tc0)
3281           call theteng(0.0d0,thet_pred_mean,theta0(it),f1,fprim1,E_tc1)
3282           call spline1(theta(i),delta,-delta,f0,f1,fprim0,ethetai,
3283      &        E_theta)
3284           call mixder(delta,thet_pred_mean,theta0(it),fprim_tc0)
3285           call spline2(theta(i),delta,-delta,E_tc0,E_tc1,fprim_tc0,
3286      &        E_tc)
3287         else
3288           call theteng(theta(i),thet_pred_mean,theta0(it),ethetai,
3289      &        E_theta,E_tc)
3290         endif
3291         etheta=etheta+ethetai
3292 c        write (iout,'(2i3,3f8.3,f10.5)') i,it,rad2deg*theta(i),
3293 c     &    rad2deg*phii,rad2deg*phii1,ethetai
3294         if (i.gt.3) gloc(i-3,icg)=gloc(i-3,icg)+wang*E_tc*dthetg1
3295         if (i.lt.nres) gloc(i-2,icg)=gloc(i-2,icg)+wang*E_tc*dthetg2
3296         gloc(nphi+i-2,icg)=wang*(E_theta+E_tc*dthett)
3297  1215   continue
3298       enddo
3299 C Ufff.... We've done all this!!!
3300       return
3301       end
3302 C---------------------------------------------------------------------------
3303       subroutine theteng(thetai,thet_pred_mean,theta0i,ethetai,E_theta,
3304      &     E_tc)
3305       implicit real*8 (a-h,o-z)
3306       include 'DIMENSIONS'
3307       include 'COMMON.LOCAL'
3308       include 'COMMON.IOUNITS'
3309       common /calcthet/ term1,term2,termm,diffak,ratak,
3310      & ak,aktc,termpre,termexp,sigc,sig0i,time11,time12,sigcsq,
3311      & delthe0,sig0inv,sigtc,sigsqtc,delthec,it
3312 C Calculate the contributions to both Gaussian lobes.
3313 C 6/6/97 - Deform the Gaussians using the factor of 1/(1+time)
3314 C The "polynomial part" of the "standard deviation" of this part of
3315 C the distribution.
3316         sig=polthet(3,it)
3317         do j=2,0,-1
3318           sig=sig*thet_pred_mean+polthet(j,it)
3319         enddo
3320 C Derivative of the "interior part" of the "standard deviation of the"
3321 C gamma-dependent Gaussian lobe in t_c.
3322         sigtc=3*polthet(3,it)
3323         do j=2,1,-1
3324           sigtc=sigtc*thet_pred_mean+j*polthet(j,it)
3325         enddo
3326         sigtc=sig*sigtc
3327 C Set the parameters of both Gaussian lobes of the distribution.
3328 C "Standard deviation" of the gamma-dependent Gaussian lobe (sigtc)
3329         fac=sig*sig+sigc0(it)
3330         sigcsq=fac+fac
3331         sigc=1.0D0/sigcsq
3332 C Following variable (sigsqtc) is -(1/2)d[sigma(t_c)**(-2))]/dt_c
3333         sigsqtc=-4.0D0*sigcsq*sigtc
3334 c       print *,i,sig,sigtc,sigsqtc
3335 C Following variable (sigtc) is d[sigma(t_c)]/dt_c
3336         sigtc=-sigtc/(fac*fac)
3337 C Following variable is sigma(t_c)**(-2)
3338         sigcsq=sigcsq*sigcsq
3339         sig0i=sig0(it)
3340         sig0inv=1.0D0/sig0i**2
3341         delthec=thetai-thet_pred_mean
3342         delthe0=thetai-theta0i
3343         term1=-0.5D0*sigcsq*delthec*delthec
3344         term2=-0.5D0*sig0inv*delthe0*delthe0
3345 C Following fuzzy logic is to avoid underflows in dexp and subsequent INFs and
3346 C NaNs in taking the logarithm. We extract the largest exponent which is added
3347 C to the energy (this being the log of the distribution) at the end of energy
3348 C term evaluation for this virtual-bond angle.
3349         if (term1.gt.term2) then
3350           termm=term1
3351           term2=dexp(term2-termm)
3352           term1=1.0d0
3353         else
3354           termm=term2
3355           term1=dexp(term1-termm)
3356           term2=1.0d0
3357         endif
3358 C The ratio between the gamma-independent and gamma-dependent lobes of
3359 C the distribution is a Gaussian function of thet_pred_mean too.
3360         diffak=gthet(2,it)-thet_pred_mean
3361         ratak=diffak/gthet(3,it)**2
3362         ak=dexp(gthet(1,it)-0.5D0*diffak*ratak)
3363 C Let's differentiate it in thet_pred_mean NOW.
3364         aktc=ak*ratak
3365 C Now put together the distribution terms to make complete distribution.
3366         termexp=term1+ak*term2
3367         termpre=sigc+ak*sig0i
3368 C Contribution of the bending energy from this theta is just the -log of
3369 C the sum of the contributions from the two lobes and the pre-exponential
3370 C factor. Simple enough, isn't it?
3371         ethetai=(-dlog(termexp)-termm+dlog(termpre))
3372 C NOW the derivatives!!!
3373 C 6/6/97 Take into account the deformation.
3374         E_theta=(delthec*sigcsq*term1
3375      &       +ak*delthe0*sig0inv*term2)/termexp
3376         E_tc=((sigtc+aktc*sig0i)/termpre
3377      &      -((delthec*sigcsq+delthec*delthec*sigsqtc)*term1+
3378      &       aktc*term2)/termexp)
3379       return
3380       end
3381 c-----------------------------------------------------------------------------
3382       subroutine mixder(thetai,thet_pred_mean,theta0i,E_tc_t)
3383       implicit real*8 (a-h,o-z)
3384       include 'DIMENSIONS'
3385       include 'COMMON.LOCAL'
3386       include 'COMMON.IOUNITS'
3387       common /calcthet/ term1,term2,termm,diffak,ratak,
3388      & ak,aktc,termpre,termexp,sigc,sig0i,time11,time12,sigcsq,
3389      & delthe0,sig0inv,sigtc,sigsqtc,delthec,it
3390       delthec=thetai-thet_pred_mean
3391       delthe0=thetai-theta0i
3392 C "Thank you" to MAPLE (probably spared one day of hand-differentiation).
3393       t3 = thetai-thet_pred_mean
3394       t6 = t3**2
3395       t9 = term1
3396       t12 = t3*sigcsq
3397       t14 = t12+t6*sigsqtc
3398       t16 = 1.0d0
3399       t21 = thetai-theta0i
3400       t23 = t21**2
3401       t26 = term2
3402       t27 = t21*t26
3403       t32 = termexp
3404       t40 = t32**2
3405       E_tc_t = -((sigcsq+2.D0*t3*sigsqtc)*t9-t14*sigcsq*t3*t16*t9
3406      & -aktc*sig0inv*t27)/t32+(t14*t9+aktc*t26)/t40
3407      & *(-t12*t9-ak*sig0inv*t27)
3408       return
3409       end
3410 #else
3411 C--------------------------------------------------------------------------
3412       subroutine ebend(etheta)
3413 C
3414 C Evaluate the virtual-bond-angle energy given the virtual-bond dihedral
3415 C angles gamma and its derivatives in consecutive thetas and gammas.
3416 C ab initio-derived potentials from
3417 c Kozlowska et al., J. Phys.: Condens. Matter 19 (2007) 285203
3418 C
3419       implicit real*8 (a-h,o-z)
3420       include 'DIMENSIONS'
3421       include 'DIMENSIONS.ZSCOPT'
3422       include 'COMMON.LOCAL'
3423       include 'COMMON.GEO'
3424       include 'COMMON.INTERACT'
3425       include 'COMMON.DERIV'
3426       include 'COMMON.VAR'
3427       include 'COMMON.CHAIN'
3428       include 'COMMON.IOUNITS'
3429       include 'COMMON.NAMES'
3430       include 'COMMON.FFIELD'
3431       include 'COMMON.CONTROL'
3432       double precision coskt(mmaxtheterm),sinkt(mmaxtheterm),
3433      & cosph1(maxsingle),sinph1(maxsingle),cosph2(maxsingle),
3434      & sinph2(maxsingle),cosph1ph2(maxdouble,maxdouble),
3435      & sinph1ph2(maxdouble,maxdouble)
3436       logical lprn /.false./, lprn1 /.false./
3437       etheta=0.0D0
3438 c      write (iout,*) "ithetyp",(ithetyp(i),i=1,ntyp1)
3439       do i=ithet_start,ithet_end
3440         if ((itype(i-1).eq.ntyp1).or.(itype(i-2).eq.ntyp1).or.
3441      &(itype(i).eq.ntyp1)) cycle
3442         dethetai=0.0d0
3443         dephii=0.0d0
3444         dephii1=0.0d0
3445         theti2=0.5d0*theta(i)
3446         ityp2=ithetyp(itype(i-1))
3447         do k=1,nntheterm
3448           coskt(k)=dcos(k*theti2)
3449           sinkt(k)=dsin(k*theti2)
3450         enddo
3451         if (i.gt.3 .and. itype(max0(i-3,1)).ne.ntyp1) then
3452 #ifdef OSF
3453           phii=phi(i)
3454           if (phii.ne.phii) phii=150.0
3455 #else
3456           phii=phi(i)
3457 #endif
3458           ityp1=ithetyp(itype(i-2))
3459           do k=1,nsingle
3460             cosph1(k)=dcos(k*phii)
3461             sinph1(k)=dsin(k*phii)
3462           enddo
3463         else
3464           phii=0.0d0
3465           ityp1=ithetyp(itype(i-2))
3466           do k=1,nsingle
3467             cosph1(k)=0.0d0
3468             sinph1(k)=0.0d0
3469           enddo
3470         endif
3471         if (i.lt.nres .and. itype(i+1).ne.ntyp1) then
3472 #ifdef OSF
3473           phii1=phi(i+1)
3474           if (phii1.ne.phii1) phii1=150.0
3475           phii1=pinorm(phii1)
3476 #else
3477           phii1=phi(i+1)
3478 #endif
3479           ityp3=ithetyp(itype(i))
3480           do k=1,nsingle
3481             cosph2(k)=dcos(k*phii1)
3482             sinph2(k)=dsin(k*phii1)
3483           enddo
3484         else
3485           phii1=0.0d0
3486           ityp3=ithetyp(itype(i))
3487           do k=1,nsingle
3488             cosph2(k)=0.0d0
3489             sinph2(k)=0.0d0
3490           enddo
3491         endif
3492 c        write (iout,*) "i",i," ityp1",itype(i-2),ityp1,
3493 c     &   " ityp2",itype(i-1),ityp2," ityp3",itype(i),ityp3
3494 c        call flush(iout)
3495         ethetai=aa0thet(ityp1,ityp2,ityp3)
3496         do k=1,ndouble
3497           do l=1,k-1
3498             ccl=cosph1(l)*cosph2(k-l)
3499             ssl=sinph1(l)*sinph2(k-l)
3500             scl=sinph1(l)*cosph2(k-l)
3501             csl=cosph1(l)*sinph2(k-l)
3502             cosph1ph2(l,k)=ccl-ssl
3503             cosph1ph2(k,l)=ccl+ssl
3504             sinph1ph2(l,k)=scl+csl
3505             sinph1ph2(k,l)=scl-csl
3506           enddo
3507         enddo
3508         if (lprn) then
3509         write (iout,*) "i",i," ityp1",ityp1," ityp2",ityp2,
3510      &    " ityp3",ityp3," theti2",theti2," phii",phii," phii1",phii1
3511         write (iout,*) "coskt and sinkt"
3512         do k=1,nntheterm
3513           write (iout,*) k,coskt(k),sinkt(k)
3514         enddo
3515         endif
3516         do k=1,ntheterm
3517           ethetai=ethetai+aathet(k,ityp1,ityp2,ityp3)*sinkt(k)
3518           dethetai=dethetai+0.5d0*k*aathet(k,ityp1,ityp2,ityp3)
3519      &      *coskt(k)
3520           if (lprn)
3521      &    write (iout,*) "k",k," aathet",aathet(k,ityp1,ityp2,ityp3),
3522      &     " ethetai",ethetai
3523         enddo
3524         if (lprn) then
3525         write (iout,*) "cosph and sinph"
3526         do k=1,nsingle
3527           write (iout,*) k,cosph1(k),sinph1(k),cosph2(k),sinph2(k)
3528         enddo
3529         write (iout,*) "cosph1ph2 and sinph2ph2"
3530         do k=2,ndouble
3531           do l=1,k-1
3532             write (iout,*) l,k,cosph1ph2(l,k),cosph1ph2(k,l),
3533      &         sinph1ph2(l,k),sinph1ph2(k,l)
3534           enddo
3535         enddo
3536         write(iout,*) "ethetai",ethetai
3537         endif
3538         do m=1,ntheterm2
3539           do k=1,nsingle
3540             aux=bbthet(k,m,ityp1,ityp2,ityp3)*cosph1(k)
3541      &         +ccthet(k,m,ityp1,ityp2,ityp3)*sinph1(k)
3542      &         +ddthet(k,m,ityp1,ityp2,ityp3)*cosph2(k)
3543      &         +eethet(k,m,ityp1,ityp2,ityp3)*sinph2(k)
3544             ethetai=ethetai+sinkt(m)*aux
3545             dethetai=dethetai+0.5d0*m*aux*coskt(m)
3546             dephii=dephii+k*sinkt(m)*(
3547      &          ccthet(k,m,ityp1,ityp2,ityp3)*cosph1(k)-
3548      &          bbthet(k,m,ityp1,ityp2,ityp3)*sinph1(k))
3549             dephii1=dephii1+k*sinkt(m)*(
3550      &          eethet(k,m,ityp1,ityp2,ityp3)*cosph2(k)-
3551      &          ddthet(k,m,ityp1,ityp2,ityp3)*sinph2(k))
3552             if (lprn)
3553      &      write (iout,*) "m",m," k",k," bbthet",
3554      &         bbthet(k,m,ityp1,ityp2,ityp3)," ccthet",
3555      &         ccthet(k,m,ityp1,ityp2,ityp3)," ddthet",
3556      &         ddthet(k,m,ityp1,ityp2,ityp3)," eethet",
3557      &         eethet(k,m,ityp1,ityp2,ityp3)," ethetai",ethetai
3558           enddo
3559         enddo
3560         if (lprn)
3561      &  write(iout,*) "ethetai",ethetai
3562         do m=1,ntheterm3
3563           do k=2,ndouble
3564             do l=1,k-1
3565               aux=ffthet(l,k,m,ityp1,ityp2,ityp3)*cosph1ph2(l,k)+
3566      &            ffthet(k,l,m,ityp1,ityp2,ityp3)*cosph1ph2(k,l)+
3567      &            ggthet(l,k,m,ityp1,ityp2,ityp3)*sinph1ph2(l,k)+
3568      &            ggthet(k,l,m,ityp1,ityp2,ityp3)*sinph1ph2(k,l)
3569               ethetai=ethetai+sinkt(m)*aux
3570               dethetai=dethetai+0.5d0*m*coskt(m)*aux
3571               dephii=dephii+l*sinkt(m)*(
3572      &           -ffthet(l,k,m,ityp1,ityp2,ityp3)*sinph1ph2(l,k)-
3573      &            ffthet(k,l,m,ityp1,ityp2,ityp3)*sinph1ph2(k,l)+
3574      &            ggthet(l,k,m,ityp1,ityp2,ityp3)*cosph1ph2(l,k)+
3575      &            ggthet(k,l,m,ityp1,ityp2,ityp3)*cosph1ph2(k,l))
3576               dephii1=dephii1+(k-l)*sinkt(m)*(
3577      &           -ffthet(l,k,m,ityp1,ityp2,ityp3)*sinph1ph2(l,k)+
3578      &            ffthet(k,l,m,ityp1,ityp2,ityp3)*sinph1ph2(k,l)+
3579      &            ggthet(l,k,m,ityp1,ityp2,ityp3)*cosph1ph2(l,k)-
3580      &            ggthet(k,l,m,ityp1,ityp2,ityp3)*cosph1ph2(k,l))
3581               if (lprn) then
3582               write (iout,*) "m",m," k",k," l",l," ffthet",
3583      &            ffthet(l,k,m,ityp1,ityp2,ityp3),
3584      &            ffthet(k,l,m,ityp1,ityp2,ityp3)," ggthet",
3585      &            ggthet(l,k,m,ityp1,ityp2,ityp3),
3586      &            ggthet(k,l,m,ityp1,ityp2,ityp3)," ethetai",ethetai
3587               write (iout,*) cosph1ph2(l,k)*sinkt(m),
3588      &            cosph1ph2(k,l)*sinkt(m),
3589      &            sinph1ph2(l,k)*sinkt(m),sinph1ph2(k,l)*sinkt(m)
3590               endif
3591             enddo
3592           enddo
3593         enddo
3594 10      continue
3595 c        lprn1=.true.
3596         if (lprn1) write (iout,'(a4,i2,3f8.1,9h ethetai ,f10.5)')
3597      &  'ebe',i,theta(i)*rad2deg,phii*rad2deg,
3598      &   phii1*rad2deg,ethetai
3599 c        lprn1=.false.
3600         etheta=etheta+ethetai
3601
3602         if (i.gt.3) gloc(i-3,icg)=gloc(i-3,icg)+wang*dephii
3603         if (i.lt.nres) gloc(i-2,icg)=gloc(i-2,icg)+wang*dephii1
3604         gloc(nphi+i-2,icg)=wang*dethetai
3605       enddo
3606       return
3607       end
3608 #endif
3609 #ifdef CRYST_SC
3610 c-----------------------------------------------------------------------------
3611       subroutine esc(escloc)
3612 C Calculate the local energy of a side chain and its derivatives in the
3613 C corresponding virtual-bond valence angles THETA and the spherical angles
3614 C ALPHA and OMEGA.
3615       implicit real*8 (a-h,o-z)
3616       include 'DIMENSIONS'
3617       include 'DIMENSIONS.ZSCOPT'
3618       include 'COMMON.GEO'
3619       include 'COMMON.LOCAL'
3620       include 'COMMON.VAR'
3621       include 'COMMON.INTERACT'
3622       include 'COMMON.DERIV'
3623       include 'COMMON.CHAIN'
3624       include 'COMMON.IOUNITS'
3625       include 'COMMON.NAMES'
3626       include 'COMMON.FFIELD'
3627       double precision x(3),dersc(3),xemp(3),dersc0(3),dersc1(3),
3628      &     ddersc0(3),ddummy(3),xtemp(3),temp(3)
3629       common /sccalc/ time11,time12,time112,theti,it,nlobit
3630       delta=0.02d0*pi
3631       escloc=0.0D0
3632 c     write (iout,'(a)') 'ESC'
3633       do i=loc_start,loc_end
3634         it=itype(i)
3635         if (it.eq.10) goto 1
3636         nlobit=nlob(it)
3637 c       print *,'i=',i,' it=',it,' nlobit=',nlobit
3638 c       write (iout,*) 'i=',i,' ssa=',ssa,' ssad=',ssad
3639         theti=theta(i+1)-pipol
3640         x(1)=dtan(theti)
3641         x(2)=alph(i)
3642         x(3)=omeg(i)
3643 c        write (iout,*) "i",i," x",x(1),x(2),x(3)
3644
3645         if (x(2).gt.pi-delta) then
3646           xtemp(1)=x(1)
3647           xtemp(2)=pi-delta
3648           xtemp(3)=x(3)
3649           call enesc(xtemp,escloci0,dersc0,ddersc0,.true.)
3650           xtemp(2)=pi
3651           call enesc(xtemp,escloci1,dersc1,ddummy,.false.)
3652           call spline1(x(2),pi-delta,delta,escloci0,escloci1,dersc0(2),
3653      &        escloci,dersc(2))
3654           call spline2(x(2),pi-delta,delta,dersc0(1),dersc1(1),
3655      &        ddersc0(1),dersc(1))
3656           call spline2(x(2),pi-delta,delta,dersc0(3),dersc1(3),
3657      &        ddersc0(3),dersc(3))
3658           xtemp(2)=pi-delta
3659           call enesc_bound(xtemp,esclocbi0,dersc0,dersc12,.true.)
3660           xtemp(2)=pi
3661           call enesc_bound(xtemp,esclocbi1,dersc1,chuju,.false.)
3662           call spline1(x(2),pi-delta,delta,esclocbi0,esclocbi1,
3663      &            dersc0(2),esclocbi,dersc02)
3664           call spline2(x(2),pi-delta,delta,dersc0(1),dersc1(1),
3665      &            dersc12,dersc01)
3666           call splinthet(x(2),0.5d0*delta,ss,ssd)
3667           dersc0(1)=dersc01
3668           dersc0(2)=dersc02
3669           dersc0(3)=0.0d0
3670           do k=1,3
3671             dersc(k)=ss*dersc(k)+(1.0d0-ss)*dersc0(k)
3672           enddo
3673           dersc(2)=dersc(2)+ssd*(escloci-esclocbi)
3674 c         write (iout,*) 'i=',i,x(2)*rad2deg,escloci0,escloci,
3675 c    &             esclocbi,ss,ssd
3676           escloci=ss*escloci+(1.0d0-ss)*esclocbi
3677 c         escloci=esclocbi
3678 c         write (iout,*) escloci
3679         else if (x(2).lt.delta) then
3680           xtemp(1)=x(1)
3681           xtemp(2)=delta
3682           xtemp(3)=x(3)
3683           call enesc(xtemp,escloci0,dersc0,ddersc0,.true.)
3684           xtemp(2)=0.0d0
3685           call enesc(xtemp,escloci1,dersc1,ddummy,.false.)
3686           call spline1(x(2),delta,-delta,escloci0,escloci1,dersc0(2),
3687      &        escloci,dersc(2))
3688           call spline2(x(2),delta,-delta,dersc0(1),dersc1(1),
3689      &        ddersc0(1),dersc(1))
3690           call spline2(x(2),delta,-delta,dersc0(3),dersc1(3),
3691      &        ddersc0(3),dersc(3))
3692           xtemp(2)=delta
3693           call enesc_bound(xtemp,esclocbi0,dersc0,dersc12,.true.)
3694           xtemp(2)=0.0d0
3695           call enesc_bound(xtemp,esclocbi1,dersc1,chuju,.false.)
3696           call spline1(x(2),delta,-delta,esclocbi0,esclocbi1,
3697      &            dersc0(2),esclocbi,dersc02)
3698           call spline2(x(2),delta,-delta,dersc0(1),dersc1(1),
3699      &            dersc12,dersc01)
3700           dersc0(1)=dersc01
3701           dersc0(2)=dersc02
3702           dersc0(3)=0.0d0
3703           call splinthet(x(2),0.5d0*delta,ss,ssd)
3704           do k=1,3
3705             dersc(k)=ss*dersc(k)+(1.0d0-ss)*dersc0(k)
3706           enddo
3707           dersc(2)=dersc(2)+ssd*(escloci-esclocbi)
3708 c         write (iout,*) 'i=',i,x(2)*rad2deg,escloci0,escloci,
3709 c    &             esclocbi,ss,ssd
3710           escloci=ss*escloci+(1.0d0-ss)*esclocbi
3711 c         write (iout,*) escloci
3712         else
3713           call enesc(x,escloci,dersc,ddummy,.false.)
3714         endif
3715
3716         escloc=escloc+escloci
3717 c        write (iout,*) 'i=',i,' escloci=',escloci,' dersc=',dersc
3718
3719         gloc(nphi+i-1,icg)=gloc(nphi+i-1,icg)+
3720      &   wscloc*dersc(1)
3721         gloc(ialph(i,1),icg)=wscloc*dersc(2)
3722         gloc(ialph(i,1)+nside,icg)=wscloc*dersc(3)
3723     1   continue
3724       enddo
3725       return
3726       end
3727 C---------------------------------------------------------------------------
3728       subroutine enesc(x,escloci,dersc,ddersc,mixed)
3729       implicit real*8 (a-h,o-z)
3730       include 'DIMENSIONS'
3731       include 'COMMON.GEO'
3732       include 'COMMON.LOCAL'
3733       include 'COMMON.IOUNITS'
3734       common /sccalc/ time11,time12,time112,theti,it,nlobit
3735       double precision x(3),z(3),Ax(3,maxlob,-1:1),dersc(3),ddersc(3)
3736       double precision contr(maxlob,-1:1)
3737       logical mixed
3738 c       write (iout,*) 'it=',it,' nlobit=',nlobit
3739         escloc_i=0.0D0
3740         do j=1,3
3741           dersc(j)=0.0D0
3742           if (mixed) ddersc(j)=0.0d0
3743         enddo
3744         x3=x(3)
3745
3746 C Because of periodicity of the dependence of the SC energy in omega we have
3747 C to add up the contributions from x(3)-2*pi, x(3), and x(3+2*pi).
3748 C To avoid underflows, first compute & store the exponents.
3749
3750         do iii=-1,1
3751
3752           x(3)=x3+iii*dwapi
3753
3754           do j=1,nlobit
3755             do k=1,3
3756               z(k)=x(k)-censc(k,j,it)
3757             enddo
3758             do k=1,3
3759               Axk=0.0D0
3760               do l=1,3
3761                 Axk=Axk+gaussc(l,k,j,it)*z(l)
3762               enddo
3763               Ax(k,j,iii)=Axk
3764             enddo
3765             expfac=0.0D0
3766             do k=1,3
3767               expfac=expfac+Ax(k,j,iii)*z(k)
3768             enddo
3769             contr(j,iii)=expfac
3770           enddo ! j
3771
3772         enddo ! iii
3773
3774         x(3)=x3
3775 C As in the case of ebend, we want to avoid underflows in exponentiation and
3776 C subsequent NaNs and INFs in energy calculation.
3777 C Find the largest exponent
3778         emin=contr(1,-1)
3779         do iii=-1,1
3780           do j=1,nlobit
3781             if (emin.gt.contr(j,iii)) emin=contr(j,iii)
3782           enddo
3783         enddo
3784         emin=0.5D0*emin
3785 cd      print *,'it=',it,' emin=',emin
3786
3787 C Compute the contribution to SC energy and derivatives
3788         do iii=-1,1
3789
3790           do j=1,nlobit
3791             expfac=dexp(bsc(j,it)-0.5D0*contr(j,iii)+emin)
3792 cd          print *,'j=',j,' expfac=',expfac
3793             escloc_i=escloc_i+expfac
3794             do k=1,3
3795               dersc(k)=dersc(k)+Ax(k,j,iii)*expfac
3796             enddo
3797             if (mixed) then
3798               do k=1,3,2
3799                 ddersc(k)=ddersc(k)+(-Ax(2,j,iii)*Ax(k,j,iii)
3800      &            +gaussc(k,2,j,it))*expfac
3801               enddo
3802             endif
3803           enddo
3804
3805         enddo ! iii
3806
3807         dersc(1)=dersc(1)/cos(theti)**2
3808         ddersc(1)=ddersc(1)/cos(theti)**2
3809         ddersc(3)=ddersc(3)
3810
3811         escloci=-(dlog(escloc_i)-emin)
3812         do j=1,3
3813           dersc(j)=dersc(j)/escloc_i
3814         enddo
3815         if (mixed) then
3816           do j=1,3,2
3817             ddersc(j)=(ddersc(j)/escloc_i+dersc(2)*dersc(j))
3818           enddo
3819         endif
3820       return
3821       end
3822 C------------------------------------------------------------------------------
3823       subroutine enesc_bound(x,escloci,dersc,dersc12,mixed)
3824       implicit real*8 (a-h,o-z)
3825       include 'DIMENSIONS'
3826       include 'COMMON.GEO'
3827       include 'COMMON.LOCAL'
3828       include 'COMMON.IOUNITS'
3829       common /sccalc/ time11,time12,time112,theti,it,nlobit
3830       double precision x(3),z(3),Ax(3,maxlob),dersc(3)
3831       double precision contr(maxlob)
3832       logical mixed
3833
3834       escloc_i=0.0D0
3835
3836       do j=1,3
3837         dersc(j)=0.0D0
3838       enddo
3839
3840       do j=1,nlobit
3841         do k=1,2
3842           z(k)=x(k)-censc(k,j,it)
3843         enddo
3844         z(3)=dwapi
3845         do k=1,3
3846           Axk=0.0D0
3847           do l=1,3
3848             Axk=Axk+gaussc(l,k,j,it)*z(l)
3849           enddo
3850           Ax(k,j)=Axk
3851         enddo
3852         expfac=0.0D0
3853         do k=1,3
3854           expfac=expfac+Ax(k,j)*z(k)
3855         enddo
3856         contr(j)=expfac
3857       enddo ! j
3858
3859 C As in the case of ebend, we want to avoid underflows in exponentiation and
3860 C subsequent NaNs and INFs in energy calculation.
3861 C Find the largest exponent
3862       emin=contr(1)
3863       do j=1,nlobit
3864         if (emin.gt.contr(j)) emin=contr(j)
3865       enddo
3866       emin=0.5D0*emin
3867
3868 C Compute the contribution to SC energy and derivatives
3869
3870       dersc12=0.0d0
3871       do j=1,nlobit
3872         expfac=dexp(bsc(j,it)-0.5D0*contr(j)+emin)
3873         escloc_i=escloc_i+expfac
3874         do k=1,2
3875           dersc(k)=dersc(k)+Ax(k,j)*expfac
3876         enddo
3877         if (mixed) dersc12=dersc12+(-Ax(2,j)*Ax(1,j)
3878      &            +gaussc(1,2,j,it))*expfac
3879         dersc(3)=0.0d0
3880       enddo
3881
3882       dersc(1)=dersc(1)/cos(theti)**2
3883       dersc12=dersc12/cos(theti)**2
3884       escloci=-(dlog(escloc_i)-emin)
3885       do j=1,2
3886         dersc(j)=dersc(j)/escloc_i
3887       enddo
3888       if (mixed) dersc12=(dersc12/escloc_i+dersc(2)*dersc(1))
3889       return
3890       end
3891 #else
3892 c----------------------------------------------------------------------------------
3893       subroutine esc(escloc)
3894 C Calculate the local energy of a side chain and its derivatives in the
3895 C corresponding virtual-bond valence angles THETA and the spherical angles
3896 C ALPHA and OMEGA derived from AM1 all-atom calculations.
3897 C added by Urszula Kozlowska. 07/11/2007
3898 C
3899       implicit real*8 (a-h,o-z)
3900       include 'DIMENSIONS'
3901       include 'DIMENSIONS.ZSCOPT'
3902       include 'COMMON.GEO'
3903       include 'COMMON.LOCAL'
3904       include 'COMMON.VAR'
3905       include 'COMMON.SCROT'
3906       include 'COMMON.INTERACT'
3907       include 'COMMON.DERIV'
3908       include 'COMMON.CHAIN'
3909       include 'COMMON.IOUNITS'
3910       include 'COMMON.NAMES'
3911       include 'COMMON.FFIELD'
3912       include 'COMMON.CONTROL'
3913       include 'COMMON.VECTORS'
3914       double precision x_prime(3),y_prime(3),z_prime(3)
3915      &    , sumene,dsc_i,dp2_i,x(65),
3916      &     xx,yy,zz,sumene1,sumene2,sumene3,sumene4,s1,s1_6,s2,s2_6,
3917      &    de_dxx,de_dyy,de_dzz,de_dt
3918       double precision s1_t,s1_6_t,s2_t,s2_6_t
3919       double precision
3920      & dXX_Ci1(3),dYY_Ci1(3),dZZ_Ci1(3),dXX_Ci(3),
3921      & dYY_Ci(3),dZZ_Ci(3),dXX_XYZ(3),dYY_XYZ(3),dZZ_XYZ(3),
3922      & dt_dCi(3),dt_dCi1(3)
3923       common /sccalc/ time11,time12,time112,theti,it,nlobit
3924       delta=0.02d0*pi
3925       escloc=0.0D0
3926       do i=loc_start,loc_end
3927         costtab(i+1) =dcos(theta(i+1))
3928         sinttab(i+1) =dsqrt(1-costtab(i+1)*costtab(i+1))
3929         cost2tab(i+1)=dsqrt(0.5d0*(1.0d0+costtab(i+1)))
3930         sint2tab(i+1)=dsqrt(0.5d0*(1.0d0-costtab(i+1)))
3931         cosfac2=0.5d0/(1.0d0+costtab(i+1))
3932         cosfac=dsqrt(cosfac2)
3933         sinfac2=0.5d0/(1.0d0-costtab(i+1))
3934         sinfac=dsqrt(sinfac2)
3935         it=itype(i)
3936         if (it.eq.10) goto 1
3937 c
3938 C  Compute the axes of tghe local cartesian coordinates system; store in
3939 c   x_prime, y_prime and z_prime
3940 c
3941         do j=1,3
3942           x_prime(j) = 0.00
3943           y_prime(j) = 0.00
3944           z_prime(j) = 0.00
3945         enddo
3946 C        write(2,*) "dc_norm", dc_norm(1,i+nres),dc_norm(2,i+nres),
3947 C     &   dc_norm(3,i+nres)
3948         do j = 1,3
3949           x_prime(j) = (dc_norm(j,i) - dc_norm(j,i-1))*cosfac
3950           y_prime(j) = (dc_norm(j,i) + dc_norm(j,i-1))*sinfac
3951         enddo
3952         do j = 1,3
3953           z_prime(j) = -uz(j,i-1)
3954         enddo
3955 c       write (2,*) "i",i
3956 c       write (2,*) "x_prime",(x_prime(j),j=1,3)
3957 c       write (2,*) "y_prime",(y_prime(j),j=1,3)
3958 c       write (2,*) "z_prime",(z_prime(j),j=1,3)
3959 c       write (2,*) "xx",scalar(x_prime(1),x_prime(1)),
3960 c      & " xy",scalar(x_prime(1),y_prime(1)),
3961 c      & " xz",scalar(x_prime(1),z_prime(1)),
3962 c      & " yy",scalar(y_prime(1),y_prime(1)),
3963 c      & " yz",scalar(y_prime(1),z_prime(1)),
3964 c      & " zz",scalar(z_prime(1),z_prime(1))
3965 c
3966 C Transform the unit vector of the ith side-chain centroid, dC_norm(*,i),
3967 C to local coordinate system. Store in xx, yy, zz.
3968 c
3969         xx=0.0d0
3970         yy=0.0d0
3971         zz=0.0d0
3972         do j = 1,3
3973           xx = xx + x_prime(j)*dc_norm(j,i+nres)
3974           yy = yy + y_prime(j)*dc_norm(j,i+nres)
3975           zz = zz + z_prime(j)*dc_norm(j,i+nres)
3976         enddo
3977
3978         xxtab(i)=xx
3979         yytab(i)=yy
3980         zztab(i)=zz
3981 C
3982 C Compute the energy of the ith side cbain
3983 C
3984 c        write (2,*) "xx",xx," yy",yy," zz",zz
3985         it=itype(i)
3986         do j = 1,65
3987           x(j) = sc_parmin(j,it)
3988         enddo
3989 #ifdef CHECK_COORD
3990 Cc diagnostics - remove later
3991         xx1 = dcos(alph(2))
3992         yy1 = dsin(alph(2))*dcos(omeg(2))
3993         zz1 = -dsin(alph(2))*dsin(omeg(2))
3994         write(2,'(3f8.1,3f9.3,1x,3f9.3)')
3995      &    alph(2)*rad2deg,omeg(2)*rad2deg,theta(3)*rad2deg,xx,yy,zz,
3996      &    xx1,yy1,zz1
3997 C,"  --- ", xx_w,yy_w,zz_w
3998 c end diagnostics
3999 #endif
4000         sumene1= x(1)+  x(2)*xx+  x(3)*yy+  x(4)*zz+  x(5)*xx**2
4001      &   + x(6)*yy**2+  x(7)*zz**2+  x(8)*xx*zz+  x(9)*xx*yy
4002      &   + x(10)*yy*zz
4003         sumene2=  x(11) + x(12)*xx + x(13)*yy + x(14)*zz + x(15)*xx**2
4004      & + x(16)*yy**2 + x(17)*zz**2 + x(18)*xx*zz + x(19)*xx*yy
4005      & + x(20)*yy*zz
4006         sumene3=  x(21) +x(22)*xx +x(23)*yy +x(24)*zz +x(25)*xx**2
4007      &  +x(26)*yy**2 +x(27)*zz**2 +x(28)*xx*zz +x(29)*xx*yy
4008      &  +x(30)*yy*zz +x(31)*xx**3 +x(32)*yy**3 +x(33)*zz**3
4009      &  +x(34)*(xx**2)*yy +x(35)*(xx**2)*zz +x(36)*(yy**2)*xx
4010      &  +x(37)*(yy**2)*zz +x(38)*(zz**2)*xx +x(39)*(zz**2)*yy
4011      &  +x(40)*xx*yy*zz
4012         sumene4= x(41) +x(42)*xx +x(43)*yy +x(44)*zz +x(45)*xx**2
4013      &  +x(46)*yy**2 +x(47)*zz**2 +x(48)*xx*zz +x(49)*xx*yy
4014      &  +x(50)*yy*zz +x(51)*xx**3 +x(52)*yy**3 +x(53)*zz**3
4015      &  +x(54)*(xx**2)*yy +x(55)*(xx**2)*zz +x(56)*(yy**2)*xx
4016      &  +x(57)*(yy**2)*zz +x(58)*(zz**2)*xx +x(59)*(zz**2)*yy
4017      &  +x(60)*xx*yy*zz
4018         dsc_i   = 0.743d0+x(61)
4019         dp2_i   = 1.9d0+x(62)
4020         dscp1=dsqrt(dsc_i**2+dp2_i**2-2*dsc_i*dp2_i
4021      &          *(xx*cost2tab(i+1)+yy*sint2tab(i+1)))
4022         dscp2=dsqrt(dsc_i**2+dp2_i**2-2*dsc_i*dp2_i
4023      &          *(xx*cost2tab(i+1)-yy*sint2tab(i+1)))
4024         s1=(1+x(63))/(0.1d0 + dscp1)
4025         s1_6=(1+x(64))/(0.1d0 + dscp1**6)
4026         s2=(1+x(65))/(0.1d0 + dscp2)
4027         s2_6=(1+x(65))/(0.1d0 + dscp2**6)
4028         sumene = ( sumene3*sint2tab(i+1) + sumene1)*(s1+s1_6)
4029      & + (sumene4*cost2tab(i+1) +sumene2)*(s2+s2_6)
4030 c        write(2,'(i2," sumene",7f9.3)') i,sumene1,sumene2,sumene3,
4031 c     &   sumene4,
4032 c     &   dscp1,dscp2,sumene
4033 c        sumene = enesc(x,xx,yy,zz,cost2tab(i+1),sint2tab(i+1))
4034         escloc = escloc + sumene
4035 c        write (2,*) "escloc",escloc
4036         if (.not. calc_grad) goto 1
4037
4038 #ifdef DEBUG2
4039 C
4040 C This section to check the numerical derivatives of the energy of ith side
4041 C chain in xx, yy, zz, and theta. Use the -DDEBUG compiler option or insert
4042 C #define DEBUG in the code to turn it on.
4043 C
4044         write (2,*) "sumene               =",sumene
4045         aincr=1.0d-7
4046         xxsave=xx
4047         xx=xx+aincr
4048         write (2,*) xx,yy,zz
4049         sumenep = enesc(x,xx,yy,zz,cost2tab(i+1),sint2tab(i+1))
4050         de_dxx_num=(sumenep-sumene)/aincr
4051         xx=xxsave
4052         write (2,*) "xx+ sumene from enesc=",sumenep
4053         yysave=yy
4054         yy=yy+aincr
4055         write (2,*) xx,yy,zz
4056         sumenep = enesc(x,xx,yy,zz,cost2tab(i+1),sint2tab(i+1))
4057         de_dyy_num=(sumenep-sumene)/aincr
4058         yy=yysave
4059         write (2,*) "yy+ sumene from enesc=",sumenep
4060         zzsave=zz
4061         zz=zz+aincr
4062         write (2,*) xx,yy,zz
4063         sumenep = enesc(x,xx,yy,zz,cost2tab(i+1),sint2tab(i+1))
4064         de_dzz_num=(sumenep-sumene)/aincr
4065         zz=zzsave
4066         write (2,*) "zz+ sumene from enesc=",sumenep
4067         costsave=cost2tab(i+1)
4068         sintsave=sint2tab(i+1)
4069         cost2tab(i+1)=dcos(0.5d0*(theta(i+1)+aincr))
4070         sint2tab(i+1)=dsin(0.5d0*(theta(i+1)+aincr))
4071         sumenep = enesc(x,xx,yy,zz,cost2tab(i+1),sint2tab(i+1))
4072         de_dt_num=(sumenep-sumene)/aincr
4073         write (2,*) " t+ sumene from enesc=",sumenep
4074         cost2tab(i+1)=costsave
4075         sint2tab(i+1)=sintsave
4076 C End of diagnostics section.
4077 #endif
4078 C
4079 C Compute the gradient of esc
4080 C
4081         pom_s1=(1.0d0+x(63))/(0.1d0 + dscp1)**2
4082         pom_s16=6*(1.0d0+x(64))/(0.1d0 + dscp1**6)**2
4083         pom_s2=(1.0d0+x(65))/(0.1d0 + dscp2)**2
4084         pom_s26=6*(1.0d0+x(65))/(0.1d0 + dscp2**6)**2
4085         pom_dx=dsc_i*dp2_i*cost2tab(i+1)
4086         pom_dy=dsc_i*dp2_i*sint2tab(i+1)
4087         pom_dt1=-0.5d0*dsc_i*dp2_i*(xx*sint2tab(i+1)-yy*cost2tab(i+1))
4088         pom_dt2=-0.5d0*dsc_i*dp2_i*(xx*sint2tab(i+1)+yy*cost2tab(i+1))
4089         pom1=(sumene3*sint2tab(i+1)+sumene1)
4090      &     *(pom_s1/dscp1+pom_s16*dscp1**4)
4091         pom2=(sumene4*cost2tab(i+1)+sumene2)
4092      &     *(pom_s2/dscp2+pom_s26*dscp2**4)
4093         sumene1x=x(2)+2*x(5)*xx+x(8)*zz+ x(9)*yy
4094         sumene3x=x(22)+2*x(25)*xx+x(28)*zz+x(29)*yy+3*x(31)*xx**2
4095      &  +2*x(34)*xx*yy +2*x(35)*xx*zz +x(36)*(yy**2) +x(38)*(zz**2)
4096      &  +x(40)*yy*zz
4097         sumene2x=x(12)+2*x(15)*xx+x(18)*zz+ x(19)*yy
4098         sumene4x=x(42)+2*x(45)*xx +x(48)*zz +x(49)*yy +3*x(51)*xx**2
4099      &  +2*x(54)*xx*yy+2*x(55)*xx*zz+x(56)*(yy**2)+x(58)*(zz**2)
4100      &  +x(60)*yy*zz
4101         de_dxx =(sumene1x+sumene3x*sint2tab(i+1))*(s1+s1_6)
4102      &        +(sumene2x+sumene4x*cost2tab(i+1))*(s2+s2_6)
4103      &        +(pom1+pom2)*pom_dx
4104 #ifdef DEBUG
4105         write(2,*), "de_dxx = ", de_dxx,de_dxx_num
4106 #endif
4107 C
4108         sumene1y=x(3) + 2*x(6)*yy + x(9)*xx + x(10)*zz
4109         sumene3y=x(23) +2*x(26)*yy +x(29)*xx +x(30)*zz +3*x(32)*yy**2
4110      &  +x(34)*(xx**2) +2*x(36)*yy*xx +2*x(37)*yy*zz +x(39)*(zz**2)
4111      &  +x(40)*xx*zz
4112         sumene2y=x(13) + 2*x(16)*yy + x(19)*xx + x(20)*zz
4113         sumene4y=x(43)+2*x(46)*yy+x(49)*xx +x(50)*zz
4114      &  +3*x(52)*yy**2+x(54)*xx**2+2*x(56)*yy*xx +2*x(57)*yy*zz
4115      &  +x(59)*zz**2 +x(60)*xx*zz
4116         de_dyy =(sumene1y+sumene3y*sint2tab(i+1))*(s1+s1_6)
4117      &        +(sumene2y+sumene4y*cost2tab(i+1))*(s2+s2_6)
4118      &        +(pom1-pom2)*pom_dy
4119 #ifdef DEBUG
4120         write(2,*), "de_dyy = ", de_dyy,de_dyy_num
4121 #endif
4122 C
4123         de_dzz =(x(24) +2*x(27)*zz +x(28)*xx +x(30)*yy
4124      &  +3*x(33)*zz**2 +x(35)*xx**2 +x(37)*yy**2 +2*x(38)*zz*xx
4125      &  +2*x(39)*zz*yy +x(40)*xx*yy)*sint2tab(i+1)*(s1+s1_6)
4126      &  +(x(4) + 2*x(7)*zz+  x(8)*xx + x(10)*yy)*(s1+s1_6)
4127      &  +(x(44)+2*x(47)*zz +x(48)*xx   +x(50)*yy  +3*x(53)*zz**2
4128      &  +x(55)*xx**2 +x(57)*(yy**2)+2*x(58)*zz*xx +2*x(59)*zz*yy
4129      &  +x(60)*xx*yy)*cost2tab(i+1)*(s2+s2_6)
4130      &  + ( x(14) + 2*x(17)*zz+  x(18)*xx + x(20)*yy)*(s2+s2_6)
4131 #ifdef DEBUG
4132         write(2,*), "de_dzz = ", de_dzz,de_dzz_num
4133 #endif
4134 C
4135         de_dt =  0.5d0*sumene3*cost2tab(i+1)*(s1+s1_6)
4136      &  -0.5d0*sumene4*sint2tab(i+1)*(s2+s2_6)
4137      &  +pom1*pom_dt1+pom2*pom_dt2
4138 #ifdef DEBUG
4139         write(2,*), "de_dt = ", de_dt,de_dt_num
4140 #endif
4141 c
4142 C
4143        cossc=scalar(dc_norm(1,i),dc_norm(1,i+nres))
4144        cossc1=scalar(dc_norm(1,i-1),dc_norm(1,i+nres))
4145        cosfac2xx=cosfac2*xx
4146        sinfac2yy=sinfac2*yy
4147        do k = 1,3
4148          dt_dCi(k) = -(dc_norm(k,i-1)+costtab(i+1)*dc_norm(k,i))*
4149      &      vbld_inv(i+1)
4150          dt_dCi1(k)= -(dc_norm(k,i)+costtab(i+1)*dc_norm(k,i-1))*
4151      &      vbld_inv(i)
4152          pom=(dC_norm(k,i+nres)-cossc*dC_norm(k,i))*vbld_inv(i+1)
4153          pom1=(dC_norm(k,i+nres)-cossc1*dC_norm(k,i-1))*vbld_inv(i)
4154 c         write (iout,*) "i",i," k",k," pom",pom," pom1",pom1,
4155 c     &    " dt_dCi",dt_dCi(k)," dt_dCi1",dt_dCi1(k)
4156 c         write (iout,*) "dC_norm",(dC_norm(j,i),j=1,3),
4157 c     &   (dC_norm(j,i-1),j=1,3)," vbld_inv",vbld_inv(i+1),vbld_inv(i)
4158          dXX_Ci(k)=pom*cosfac-dt_dCi(k)*cosfac2xx
4159          dXX_Ci1(k)=-pom1*cosfac-dt_dCi1(k)*cosfac2xx
4160          dYY_Ci(k)=pom*sinfac+dt_dCi(k)*sinfac2yy
4161          dYY_Ci1(k)=pom1*sinfac+dt_dCi1(k)*sinfac2yy
4162          dZZ_Ci1(k)=0.0d0
4163          dZZ_Ci(k)=0.0d0
4164          do j=1,3
4165            dZZ_Ci(k)=dZZ_Ci(k)-uzgrad(j,k,2,i-1)*dC_norm(j,i+nres)
4166            dZZ_Ci1(k)=dZZ_Ci1(k)-uzgrad(j,k,1,i-1)*dC_norm(j,i+nres)
4167          enddo
4168
4169          dXX_XYZ(k)=vbld_inv(i+nres)*(x_prime(k)-xx*dC_norm(k,i+nres))
4170          dYY_XYZ(k)=vbld_inv(i+nres)*(y_prime(k)-yy*dC_norm(k,i+nres))
4171          dZZ_XYZ(k)=vbld_inv(i+nres)*(z_prime(k)-zz*dC_norm(k,i+nres))
4172 c
4173          dt_dCi(k) = -dt_dCi(k)/sinttab(i+1)
4174          dt_dCi1(k)= -dt_dCi1(k)/sinttab(i+1)
4175        enddo
4176
4177        do k=1,3
4178          dXX_Ctab(k,i)=dXX_Ci(k)
4179          dXX_C1tab(k,i)=dXX_Ci1(k)
4180          dYY_Ctab(k,i)=dYY_Ci(k)
4181          dYY_C1tab(k,i)=dYY_Ci1(k)
4182          dZZ_Ctab(k,i)=dZZ_Ci(k)
4183          dZZ_C1tab(k,i)=dZZ_Ci1(k)
4184          dXX_XYZtab(k,i)=dXX_XYZ(k)
4185          dYY_XYZtab(k,i)=dYY_XYZ(k)
4186          dZZ_XYZtab(k,i)=dZZ_XYZ(k)
4187        enddo
4188
4189        do k = 1,3
4190 c         write (iout,*) "k",k," dxx_ci1",dxx_ci1(k)," dyy_ci1",
4191 c     &    dyy_ci1(k)," dzz_ci1",dzz_ci1(k)
4192 c         write (iout,*) "k",k," dxx_ci",dxx_ci(k)," dyy_ci",
4193 c     &    dyy_ci(k)," dzz_ci",dzz_ci(k)
4194 c         write (iout,*) "k",k," dt_dci",dt_dci(k)," dt_dci",
4195 c     &    dt_dci(k)
4196 c         write (iout,*) "k",k," dxx_XYZ",dxx_XYZ(k)," dyy_XYZ",
4197 c     &    dyy_XYZ(k)," dzz_XYZ",dzz_XYZ(k)
4198          gscloc(k,i-1)=gscloc(k,i-1)+de_dxx*dxx_ci1(k)
4199      &    +de_dyy*dyy_ci1(k)+de_dzz*dzz_ci1(k)+de_dt*dt_dCi1(k)
4200          gscloc(k,i)=gscloc(k,i)+de_dxx*dxx_Ci(k)
4201      &    +de_dyy*dyy_Ci(k)+de_dzz*dzz_Ci(k)+de_dt*dt_dCi(k)
4202          gsclocx(k,i)=                 de_dxx*dxx_XYZ(k)
4203      &    +de_dyy*dyy_XYZ(k)+de_dzz*dzz_XYZ(k)
4204        enddo
4205 c       write(iout,*) "ENERGY GRAD = ", (gscloc(k,i-1),k=1,3),
4206 c     &  (gscloc(k,i),k=1,3),(gsclocx(k,i),k=1,3)
4207
4208 C to check gradient call subroutine check_grad
4209
4210     1 continue
4211       enddo
4212       return
4213       end
4214 #endif
4215 c------------------------------------------------------------------------------
4216       subroutine gcont(rij,r0ij,eps0ij,delta,fcont,fprimcont)
4217 C
4218 C This procedure calculates two-body contact function g(rij) and its derivative:
4219 C
4220 C           eps0ij                                     !       x < -1
4221 C g(rij) =  esp0ij*(-0.9375*x+0.625*x**3-0.1875*x**5)  ! -1 =< x =< 1
4222 C            0                                         !       x > 1
4223 C
4224 C where x=(rij-r0ij)/delta
4225 C
4226 C rij - interbody distance, r0ij - contact distance, eps0ij - contact energy
4227 C
4228       implicit none
4229       double precision rij,r0ij,eps0ij,fcont,fprimcont
4230       double precision x,x2,x4,delta
4231 c     delta=0.02D0*r0ij
4232 c      delta=0.2D0*r0ij
4233       x=(rij-r0ij)/delta
4234       if (x.lt.-1.0D0) then
4235         fcont=eps0ij
4236         fprimcont=0.0D0
4237       else if (x.le.1.0D0) then
4238         x2=x*x
4239         x4=x2*x2
4240         fcont=eps0ij*(x*(-0.9375D0+0.6250D0*x2-0.1875D0*x4)+0.5D0)
4241         fprimcont=eps0ij * (-0.9375D0+1.8750D0*x2-0.9375D0*x4)/delta
4242       else
4243         fcont=0.0D0
4244         fprimcont=0.0D0
4245       endif
4246       return
4247       end
4248 c------------------------------------------------------------------------------
4249       subroutine splinthet(theti,delta,ss,ssder)
4250       implicit real*8 (a-h,o-z)
4251       include 'DIMENSIONS'
4252       include 'DIMENSIONS.ZSCOPT'
4253       include 'COMMON.VAR'
4254       include 'COMMON.GEO'
4255       thetup=pi-delta
4256       thetlow=delta
4257       if (theti.gt.pipol) then
4258         call gcont(theti,thetup,1.0d0,delta,ss,ssder)
4259       else
4260         call gcont(-theti,-thetlow,1.0d0,delta,ss,ssder)
4261         ssder=-ssder
4262       endif
4263       return
4264       end
4265 c------------------------------------------------------------------------------
4266       subroutine spline1(x,x0,delta,f0,f1,fprim0,f,fprim)
4267       implicit none
4268       double precision x,x0,delta,f0,f1,fprim0,f,fprim
4269       double precision ksi,ksi2,ksi3,a1,a2,a3
4270       a1=fprim0*delta/(f1-f0)
4271       a2=3.0d0-2.0d0*a1
4272       a3=a1-2.0d0
4273       ksi=(x-x0)/delta
4274       ksi2=ksi*ksi
4275       ksi3=ksi2*ksi
4276       f=f0+(f1-f0)*ksi*(a1+ksi*(a2+a3*ksi))
4277       fprim=(f1-f0)/delta*(a1+ksi*(2*a2+3*ksi*a3))
4278       return
4279       end
4280 c------------------------------------------------------------------------------
4281       subroutine spline2(x,x0,delta,f0x,f1x,fprim0x,fx)
4282       implicit none
4283       double precision x,x0,delta,f0x,f1x,fprim0x,fx
4284       double precision ksi,ksi2,ksi3,a1,a2,a3
4285       ksi=(x-x0)/delta
4286       ksi2=ksi*ksi
4287       ksi3=ksi2*ksi
4288       a1=fprim0x*delta
4289       a2=3*(f1x-f0x)-2*fprim0x*delta
4290       a3=fprim0x*delta-2*(f1x-f0x)
4291       fx=f0x+a1*ksi+a2*ksi2+a3*ksi3
4292       return
4293       end
4294 C-----------------------------------------------------------------------------
4295 #ifdef CRYST_TOR
4296 C-----------------------------------------------------------------------------
4297       subroutine etor(etors,edihcnstr,fact)
4298       implicit real*8 (a-h,o-z)
4299       include 'DIMENSIONS'
4300       include 'DIMENSIONS.ZSCOPT'
4301       include 'COMMON.VAR'
4302       include 'COMMON.GEO'
4303       include 'COMMON.LOCAL'
4304       include 'COMMON.TORSION'
4305       include 'COMMON.INTERACT'
4306       include 'COMMON.DERIV'
4307       include 'COMMON.CHAIN'
4308       include 'COMMON.NAMES'
4309       include 'COMMON.IOUNITS'
4310       include 'COMMON.FFIELD'
4311       include 'COMMON.TORCNSTR'
4312       logical lprn
4313 C Set lprn=.true. for debugging
4314       lprn=.false.
4315 c      lprn=.true.
4316       etors=0.0D0
4317       do i=iphi_start,iphi_end
4318         itori=itortyp(itype(i-2))
4319         itori1=itortyp(itype(i-1))
4320         phii=phi(i)
4321         gloci=0.0D0
4322 C Proline-Proline pair is a special case...
4323         if (itori.eq.3 .and. itori1.eq.3) then
4324           if (phii.gt.-dwapi3) then
4325             cosphi=dcos(3*phii)
4326             fac=1.0D0/(1.0D0-cosphi)
4327             etorsi=v1(1,3,3)*fac
4328             etorsi=etorsi+etorsi
4329             etors=etors+etorsi-v1(1,3,3)
4330             gloci=gloci-3*fac*etorsi*dsin(3*phii)
4331           endif
4332           do j=1,3
4333             v1ij=v1(j+1,itori,itori1)
4334             v2ij=v2(j+1,itori,itori1)
4335             cosphi=dcos(j*phii)
4336             sinphi=dsin(j*phii)
4337             etors=etors+v1ij*cosphi+v2ij*sinphi+dabs(v1ij)+dabs(v2ij)
4338             gloci=gloci+j*(v2ij*cosphi-v1ij*sinphi)
4339           enddo
4340         else
4341           do j=1,nterm_old
4342             v1ij=v1(j,itori,itori1)
4343             v2ij=v2(j,itori,itori1)
4344             cosphi=dcos(j*phii)
4345             sinphi=dsin(j*phii)
4346             etors=etors+v1ij*cosphi+v2ij*sinphi+dabs(v1ij)+dabs(v2ij)
4347             gloci=gloci+j*(v2ij*cosphi-v1ij*sinphi)
4348           enddo
4349         endif
4350         if (lprn)
4351      &  write (iout,'(2(a3,2x,i3,2x),2i3,6f8.3/26x,6f8.3/)')
4352      &  restyp(itype(i-2)),i-2,restyp(itype(i-1)),i-1,itori,itori1,
4353      &  (v1(j,itori,itori1),j=1,6),(v2(j,itori,itori1),j=1,6)
4354         gloc(i-3,icg)=gloc(i-3,icg)+wtor*fact*gloci
4355 c       write (iout,*) 'i=',i,' gloc=',gloc(i-3,icg)
4356       enddo
4357 ! 6/20/98 - dihedral angle constraints
4358       edihcnstr=0.0d0
4359       do i=1,ndih_constr
4360         itori=idih_constr(i)
4361         phii=phi(itori)
4362         difi=phii-phi0(i)
4363         if (difi.gt.drange(i)) then
4364           difi=difi-drange(i)
4365           edihcnstr=edihcnstr+0.25d0*ftors*difi**4
4366           gloc(itori-3,icg)=gloc(itori-3,icg)+ftors*difi**3
4367         else if (difi.lt.-drange(i)) then
4368           difi=difi+drange(i)
4369           edihcnstr=edihcnstr+0.25d0*ftors*difi**4
4370           gloc(itori-3,icg)=gloc(itori-3,icg)+ftors*difi**3
4371         endif
4372 !        write (iout,'(2i5,2f8.3,2e14.5)') i,itori,rad2deg*phii,
4373 !     &    rad2deg*difi,0.25d0*ftors*difi**4,gloc(itori-3,icg)
4374       enddo
4375 !      write (iout,*) 'edihcnstr',edihcnstr
4376       return
4377       end
4378 c------------------------------------------------------------------------------
4379 #else
4380       subroutine etor(etors,edihcnstr,fact)
4381       implicit real*8 (a-h,o-z)
4382       include 'DIMENSIONS'
4383       include 'DIMENSIONS.ZSCOPT'
4384       include 'COMMON.VAR'
4385       include 'COMMON.GEO'
4386       include 'COMMON.LOCAL'
4387       include 'COMMON.TORSION'
4388       include 'COMMON.INTERACT'
4389       include 'COMMON.DERIV'
4390       include 'COMMON.CHAIN'
4391       include 'COMMON.NAMES'
4392       include 'COMMON.IOUNITS'
4393       include 'COMMON.FFIELD'
4394       include 'COMMON.TORCNSTR'
4395       logical lprn
4396 C Set lprn=.true. for debugging
4397       lprn=.false.
4398 c      lprn=.true.
4399       etors=0.0D0
4400       do i=iphi_start,iphi_end
4401         if (itel(i-2).eq.0 .or. itel(i-1).eq.0) goto 1215
4402         itori=itortyp(itype(i-2))
4403         itori1=itortyp(itype(i-1))
4404         phii=phi(i)
4405         gloci=0.0D0
4406 C Regular cosine and sine terms
4407         do j=1,nterm(itori,itori1)
4408           v1ij=v1(j,itori,itori1)
4409           v2ij=v2(j,itori,itori1)
4410           cosphi=dcos(j*phii)
4411           sinphi=dsin(j*phii)
4412           etors=etors+v1ij*cosphi+v2ij*sinphi
4413           gloci=gloci+j*(v2ij*cosphi-v1ij*sinphi)
4414         enddo
4415 C Lorentz terms
4416 C                         v1
4417 C  E = SUM ----------------------------------- - v1
4418 C          [v2 cos(phi/2)+v3 sin(phi/2)]^2 + 1
4419 C
4420         cosphi=dcos(0.5d0*phii)
4421         sinphi=dsin(0.5d0*phii)
4422         do j=1,nlor(itori,itori1)
4423           vl1ij=vlor1(j,itori,itori1)
4424           vl2ij=vlor2(j,itori,itori1)
4425           vl3ij=vlor3(j,itori,itori1)
4426           pom=vl2ij*cosphi+vl3ij*sinphi
4427           pom1=1.0d0/(pom*pom+1.0d0)
4428           etors=etors+vl1ij*pom1
4429           pom=-pom*pom1*pom1
4430           gloci=gloci+vl1ij*(vl3ij*cosphi-vl2ij*sinphi)*pom
4431         enddo
4432 C Subtract the constant term
4433         etors=etors-v0(itori,itori1)
4434         if (lprn)
4435      &  write (iout,'(2(a3,2x,i3,2x),2i3,6f8.3/26x,6f8.3/)')
4436      &  restyp(itype(i-2)),i-2,restyp(itype(i-1)),i-1,itori,itori1,
4437      &  (v1(j,itori,itori1),j=1,6),(v2(j,itori,itori1),j=1,6)
4438         gloc(i-3,icg)=gloc(i-3,icg)+wtor*fact*gloci
4439 c       write (iout,*) 'i=',i,' gloc=',gloc(i-3,icg)
4440  1215   continue
4441       enddo
4442 ! 6/20/98 - dihedral angle constraints
4443       edihcnstr=0.0d0
4444       do i=1,ndih_constr
4445         itori=idih_constr(i)
4446         phii=phi(itori)
4447         difi=pinorm(phii-phi0(i))
4448         edihi=0.0d0
4449         if (difi.gt.drange(i)) then
4450           difi=difi-drange(i)
4451           edihcnstr=edihcnstr+0.25d0*ftors*difi**4
4452           gloc(itori-3,icg)=gloc(itori-3,icg)+ftors*difi**3
4453           edihi=0.25d0*ftors*difi**4
4454         else if (difi.lt.-drange(i)) then
4455           difi=difi+drange(i)
4456           edihcnstr=edihcnstr+0.25d0*ftors*difi**4
4457           gloc(itori-3,icg)=gloc(itori-3,icg)+ftors*difi**3
4458           edihi=0.25d0*ftors*difi**4
4459         else
4460           difi=0.0d0
4461         endif
4462 c        write (iout,'(2i5,4f10.5,e15.5)') i,itori,phii,phi0(i),difi,
4463 c     &    drange(i),edihi
4464 !        write (iout,'(2i5,2f8.3,2e14.5)') i,itori,rad2deg*phii,
4465 !     &    rad2deg*difi,0.25d0*ftors*difi**4,gloc(itori-3,icg)
4466       enddo
4467 !      write (iout,*) 'edihcnstr',edihcnstr
4468       return
4469       end
4470 c----------------------------------------------------------------------------
4471       subroutine etor_d(etors_d,fact2)
4472 C 6/23/01 Compute double torsional energy
4473       implicit real*8 (a-h,o-z)
4474       include 'DIMENSIONS'
4475       include 'DIMENSIONS.ZSCOPT'
4476       include 'COMMON.VAR'
4477       include 'COMMON.GEO'
4478       include 'COMMON.LOCAL'
4479       include 'COMMON.TORSION'
4480       include 'COMMON.INTERACT'
4481       include 'COMMON.DERIV'
4482       include 'COMMON.CHAIN'
4483       include 'COMMON.NAMES'
4484       include 'COMMON.IOUNITS'
4485       include 'COMMON.FFIELD'
4486       include 'COMMON.TORCNSTR'
4487       logical lprn
4488 C Set lprn=.true. for debugging
4489       lprn=.false.
4490 c     lprn=.true.
4491       etors_d=0.0D0
4492       do i=iphi_start,iphi_end-1
4493         if (itel(i-2).eq.0 .or. itel(i-1).eq.0 .or. itel(i).eq.0)
4494      &     goto 1215
4495         itori=itortyp(itype(i-2))
4496         itori1=itortyp(itype(i-1))
4497         itori2=itortyp(itype(i))
4498         phii=phi(i)
4499         phii1=phi(i+1)
4500         gloci1=0.0D0
4501         gloci2=0.0D0
4502 C Regular cosine and sine terms
4503         do j=1,ntermd_1(itori,itori1,itori2)
4504           v1cij=v1c(1,j,itori,itori1,itori2)
4505           v1sij=v1s(1,j,itori,itori1,itori2)
4506           v2cij=v1c(2,j,itori,itori1,itori2)
4507           v2sij=v1s(2,j,itori,itori1,itori2)
4508           cosphi1=dcos(j*phii)
4509           sinphi1=dsin(j*phii)
4510           cosphi2=dcos(j*phii1)
4511           sinphi2=dsin(j*phii1)
4512           etors_d=etors_d+v1cij*cosphi1+v1sij*sinphi1+
4513      &     v2cij*cosphi2+v2sij*sinphi2
4514           gloci1=gloci1+j*(v1sij*cosphi1-v1cij*sinphi1)
4515           gloci2=gloci2+j*(v2sij*cosphi2-v2cij*sinphi2)
4516         enddo
4517         do k=2,ntermd_2(itori,itori1,itori2)
4518           do l=1,k-1
4519             v1cdij = v2c(k,l,itori,itori1,itori2)
4520             v2cdij = v2c(l,k,itori,itori1,itori2)
4521             v1sdij = v2s(k,l,itori,itori1,itori2)
4522             v2sdij = v2s(l,k,itori,itori1,itori2)
4523             cosphi1p2=dcos(l*phii+(k-l)*phii1)
4524             cosphi1m2=dcos(l*phii-(k-l)*phii1)
4525             sinphi1p2=dsin(l*phii+(k-l)*phii1)
4526             sinphi1m2=dsin(l*phii-(k-l)*phii1)
4527             etors_d=etors_d+v1cdij*cosphi1p2+v2cdij*cosphi1m2+
4528      &        v1sdij*sinphi1p2+v2sdij*sinphi1m2
4529             gloci1=gloci1+l*(v1sdij*cosphi1p2+v2sdij*cosphi1m2
4530      &        -v1cdij*sinphi1p2-v2cdij*sinphi1m2)
4531             gloci2=gloci2+(k-l)*(v1sdij*cosphi1p2-v2sdij*cosphi1m2
4532      &        -v1cdij*sinphi1p2+v2cdij*sinphi1m2)
4533           enddo
4534         enddo
4535         gloc(i-3,icg)=gloc(i-3,icg)+wtor_d*fact2*gloci1
4536         gloc(i-2,icg)=gloc(i-2,icg)+wtor_d*fact2*gloci2
4537  1215   continue
4538       enddo
4539       return
4540       end
4541 #endif
4542 c------------------------------------------------------------------------------
4543       subroutine eback_sc_corr(esccor)
4544 c 7/21/2007 Correlations between the backbone-local and side-chain-local
4545 c        conformational states; temporarily implemented as differences
4546 c        between UNRES torsional potentials (dependent on three types of
4547 c        residues) and the torsional potentials dependent on all 20 types
4548 c        of residues computed from AM1 energy surfaces of terminally-blocked
4549 c        amino-acid residues.
4550       implicit real*8 (a-h,o-z)
4551       include 'DIMENSIONS'
4552       include 'DIMENSIONS.ZSCOPT'
4553       include 'COMMON.VAR'
4554       include 'COMMON.GEO'
4555       include 'COMMON.LOCAL'
4556       include 'COMMON.TORSION'
4557       include 'COMMON.SCCOR'
4558       include 'COMMON.INTERACT'
4559       include 'COMMON.DERIV'
4560       include 'COMMON.CHAIN'
4561       include 'COMMON.NAMES'
4562       include 'COMMON.IOUNITS'
4563       include 'COMMON.FFIELD'
4564       include 'COMMON.CONTROL'
4565       logical lprn
4566 C Set lprn=.true. for debugging
4567       lprn=.false.
4568 c      lprn=.true.
4569 c      write (iout,*) "EBACK_SC_COR",itau_start,itau_end,nterm_sccor
4570       esccor=0.0D0
4571       do i=itau_start,itau_end
4572         esccor_ii=0.0D0
4573         isccori=isccortyp(itype(i-2))
4574         isccori1=isccortyp(itype(i-1))
4575         phii=phi(i)
4576 cccc  Added 9 May 2012
4577 cc Tauangle is torsional engle depending on the value of first digit
4578 c(see comment below)
4579 cc Omicron is flat angle depending on the value of first digit
4580 c(see comment below)
4581
4582
4583         do intertyp=1,3 !intertyp
4584 cc Added 09 May 2012 (Adasko)
4585 cc  Intertyp means interaction type of backbone mainchain correlation:
4586 c   1 = SC...Ca...Ca...Ca
4587 c   2 = Ca...Ca...Ca...SC
4588 c   3 = SC...Ca...Ca...SCi
4589         gloci=0.0D0
4590         if (((intertyp.eq.3).and.((itype(i-2).eq.10).or.
4591      &      (itype(i-1).eq.10).or.(itype(i-2).eq.21).or.
4592      &      (itype(i-1).eq.21)))
4593      &    .or. ((intertyp.eq.1).and.((itype(i-2).eq.10)
4594      &     .or.(itype(i-2).eq.21)))
4595      &    .or.((intertyp.eq.2).and.((itype(i-1).eq.10).or.
4596      &      (itype(i-1).eq.21)))) cycle
4597         if ((intertyp.eq.2).and.(i.eq.4).and.(itype(1).eq.21)) cycle
4598         if ((intertyp.eq.1).and.(i.eq.nres).and.(itype(nres).eq.21))
4599      & cycle
4600         do j=1,nterm_sccor(isccori,isccori1)
4601           v1ij=v1sccor(j,intertyp,isccori,isccori1)
4602           v2ij=v2sccor(j,intertyp,isccori,isccori1)
4603           cosphi=dcos(j*tauangle(intertyp,i))
4604           sinphi=dsin(j*tauangle(intertyp,i))
4605           esccor=esccor+v1ij*cosphi+v2ij*sinphi
4606 #ifdef DEBUG
4607           esccor_ii=esccor_ii+v1ij*cosphi+v2ij*sinphi
4608 #endif
4609           gloci=gloci+j*(v2ij*cosphi-v1ij*sinphi)
4610         enddo
4611         gloc_sc(intertyp,i-3,icg)=gloc_sc(intertyp,i-3,icg)+wsccor*gloci
4612 c       write (iout,*) "WTF",intertyp,i,itype(i),v1ij*cosphi+v2ij*sinphi
4613 c     &gloc_sc(intertyp,i-3,icg)
4614         if (lprn)
4615      &  write (iout,'(2(a3,2x,i3,2x),2i3,6f8.3/26x,6f8.3/)')
4616      &  restyp(itype(i-2)),i-2,restyp(itype(i-1)),i-1,itori,itori1,
4617      &  (v1sccor(j,intertyp,itori,itori1),j=1,6)
4618      & ,(v2sccor(j,intertyp,itori,itori1),j=1,6)
4619         gsccor_loc(i-3)=gsccor_loc(i-3)+gloci
4620        enddo !intertyp
4621       enddo
4622 c        do i=1,nres
4623 c        write (iout,*) "W@T@F",  gloc_sc(1,i,icg),gloc(i,icg)
4624 c        enddo
4625       return
4626       end
4627 c------------------------------------------------------------------------------
4628       subroutine multibody(ecorr)
4629 C This subroutine calculates multi-body contributions to energy following
4630 C the idea of Skolnick et al. If side chains I and J make a contact and
4631 C at the same time side chains I+1 and J+1 make a contact, an extra
4632 C contribution equal to sqrt(eps(i,j)*eps(i+1,j+1)) is added.
4633       implicit real*8 (a-h,o-z)
4634       include 'DIMENSIONS'
4635       include 'COMMON.IOUNITS'
4636       include 'COMMON.DERIV'
4637       include 'COMMON.INTERACT'
4638       include 'COMMON.CONTACTS'
4639       double precision gx(3),gx1(3)
4640       logical lprn
4641
4642 C Set lprn=.true. for debugging
4643       lprn=.false.
4644
4645       if (lprn) then
4646         write (iout,'(a)') 'Contact function values:'
4647         do i=nnt,nct-2
4648           write (iout,'(i2,20(1x,i2,f10.5))')
4649      &        i,(jcont(j,i),facont(j,i),j=1,num_cont(i))
4650         enddo
4651       endif
4652       ecorr=0.0D0
4653       do i=nnt,nct
4654         do j=1,3
4655           gradcorr(j,i)=0.0D0
4656           gradxorr(j,i)=0.0D0
4657         enddo
4658       enddo
4659       do i=nnt,nct-2
4660
4661         DO ISHIFT = 3,4
4662
4663         i1=i+ishift
4664         num_conti=num_cont(i)
4665         num_conti1=num_cont(i1)
4666         do jj=1,num_conti
4667           j=jcont(jj,i)
4668           do kk=1,num_conti1
4669             j1=jcont(kk,i1)
4670             if (j1.eq.j+ishift .or. j1.eq.j-ishift) then
4671 cd          write(iout,*)'i=',i,' j=',j,' i1=',i1,' j1=',j1,
4672 cd   &                   ' ishift=',ishift
4673 C Contacts I--J and I+ISHIFT--J+-ISHIFT1 occur simultaneously.
4674 C The system gains extra energy.
4675               ecorr=ecorr+esccorr(i,j,i1,j1,jj,kk)
4676             endif   ! j1==j+-ishift
4677           enddo     ! kk
4678         enddo       ! jj
4679
4680         ENDDO ! ISHIFT
4681
4682       enddo         ! i
4683       return
4684       end
4685 c------------------------------------------------------------------------------
4686       double precision function esccorr(i,j,k,l,jj,kk)
4687       implicit real*8 (a-h,o-z)
4688       include 'DIMENSIONS'
4689       include 'COMMON.IOUNITS'
4690       include 'COMMON.DERIV'
4691       include 'COMMON.INTERACT'
4692       include 'COMMON.CONTACTS'
4693       double precision gx(3),gx1(3)
4694       logical lprn
4695       lprn=.false.
4696       eij=facont(jj,i)
4697       ekl=facont(kk,k)
4698 cd    write (iout,'(4i5,3f10.5)') i,j,k,l,eij,ekl,-eij*ekl
4699 C Calculate the multi-body contribution to energy.
4700 C Calculate multi-body contributions to the gradient.
4701 cd    write (iout,'(2(2i3,3f10.5))')i,j,(gacont(m,jj,i),m=1,3),
4702 cd   & k,l,(gacont(m,kk,k),m=1,3)
4703       do m=1,3
4704         gx(m) =ekl*gacont(m,jj,i)
4705         gx1(m)=eij*gacont(m,kk,k)
4706         gradxorr(m,i)=gradxorr(m,i)-gx(m)
4707         gradxorr(m,j)=gradxorr(m,j)+gx(m)
4708         gradxorr(m,k)=gradxorr(m,k)-gx1(m)
4709         gradxorr(m,l)=gradxorr(m,l)+gx1(m)
4710       enddo
4711       do m=i,j-1
4712         do ll=1,3
4713           gradcorr(ll,m)=gradcorr(ll,m)+gx(ll)
4714         enddo
4715       enddo
4716       do m=k,l-1
4717         do ll=1,3
4718           gradcorr(ll,m)=gradcorr(ll,m)+gx1(ll)
4719         enddo
4720       enddo
4721       esccorr=-eij*ekl
4722       return
4723       end
4724 c------------------------------------------------------------------------------
4725 #ifdef MPL
4726       subroutine pack_buffer(dimen1,dimen2,atom,indx,buffer)
4727       implicit real*8 (a-h,o-z)
4728       include 'DIMENSIONS'
4729       integer dimen1,dimen2,atom,indx
4730       double precision buffer(dimen1,dimen2)
4731       double precision zapas
4732       common /contacts_hb/ zapas(3,20,maxres,7),
4733      &   facont_hb(20,maxres),ees0p(20,maxres),ees0m(20,maxres),
4734      &         num_cont_hb(maxres),jcont_hb(20,maxres)
4735       num_kont=num_cont_hb(atom)
4736       do i=1,num_kont
4737         do k=1,7
4738           do j=1,3
4739             buffer(i,indx+(k-1)*3+j)=zapas(j,i,atom,k)
4740           enddo ! j
4741         enddo ! k
4742         buffer(i,indx+22)=facont_hb(i,atom)
4743         buffer(i,indx+23)=ees0p(i,atom)
4744         buffer(i,indx+24)=ees0m(i,atom)
4745         buffer(i,indx+25)=dfloat(jcont_hb(i,atom))
4746       enddo ! i
4747       buffer(1,indx+26)=dfloat(num_kont)
4748       return
4749       end
4750 c------------------------------------------------------------------------------
4751       subroutine unpack_buffer(dimen1,dimen2,atom,indx,buffer)
4752       implicit real*8 (a-h,o-z)
4753       include 'DIMENSIONS'
4754       integer dimen1,dimen2,atom,indx
4755       double precision buffer(dimen1,dimen2)
4756       double precision zapas
4757       common /contacts_hb/ zapas(3,20,maxres,7),
4758      &         facont_hb(20,maxres),ees0p(20,maxres),ees0m(20,maxres),
4759      &         num_cont_hb(maxres),jcont_hb(20,maxres)
4760       num_kont=buffer(1,indx+26)
4761       num_kont_old=num_cont_hb(atom)
4762       num_cont_hb(atom)=num_kont+num_kont_old
4763       do i=1,num_kont
4764         ii=i+num_kont_old
4765         do k=1,7
4766           do j=1,3
4767             zapas(j,ii,atom,k)=buffer(i,indx+(k-1)*3+j)
4768           enddo ! j
4769         enddo ! k
4770         facont_hb(ii,atom)=buffer(i,indx+22)
4771         ees0p(ii,atom)=buffer(i,indx+23)
4772         ees0m(ii,atom)=buffer(i,indx+24)
4773         jcont_hb(ii,atom)=buffer(i,indx+25)
4774       enddo ! i
4775       return
4776       end
4777 c------------------------------------------------------------------------------
4778 #endif
4779       subroutine multibody_hb(ecorr,ecorr5,ecorr6,n_corr,n_corr1)
4780 C This subroutine calculates multi-body contributions to hydrogen-bonding
4781       implicit real*8 (a-h,o-z)
4782       include 'DIMENSIONS'
4783       include 'DIMENSIONS.ZSCOPT'
4784       include 'COMMON.IOUNITS'
4785 #ifdef MPL
4786       include 'COMMON.INFO'
4787 #endif
4788       include 'COMMON.FFIELD'
4789       include 'COMMON.DERIV'
4790       include 'COMMON.INTERACT'
4791       include 'COMMON.CONTACTS'
4792 #ifdef MPL
4793       parameter (max_cont=maxconts)
4794       parameter (max_dim=2*(8*3+2))
4795       parameter (msglen1=max_cont*max_dim*4)
4796       parameter (msglen2=2*msglen1)
4797       integer source,CorrelType,CorrelID,Error
4798       double precision buffer(max_cont,max_dim)
4799 #endif
4800       double precision gx(3),gx1(3)
4801       logical lprn,ldone
4802
4803 C Set lprn=.true. for debugging
4804       lprn=.false.
4805 #ifdef MPL
4806       n_corr=0
4807       n_corr1=0
4808       if (fgProcs.le.1) goto 30
4809       if (lprn) then
4810         write (iout,'(a)') 'Contact function values:'
4811         do i=nnt,nct-2
4812           write (iout,'(2i3,50(1x,i2,f5.2))')
4813      &    i,num_cont_hb(i),(jcont_hb(j,i),facont_hb(j,i),
4814      &    j=1,num_cont_hb(i))
4815         enddo
4816       endif
4817 C Caution! Following code assumes that electrostatic interactions concerning
4818 C a given atom are split among at most two processors!
4819       CorrelType=477
4820       CorrelID=MyID+1
4821       ldone=.false.
4822       do i=1,max_cont
4823         do j=1,max_dim
4824           buffer(i,j)=0.0D0
4825         enddo
4826       enddo
4827       mm=mod(MyRank,2)
4828 cd    write (iout,*) 'MyRank',MyRank,' mm',mm
4829       if (mm) 20,20,10
4830    10 continue
4831 cd    write (iout,*) 'Sending: MyRank',MyRank,' mm',mm,' ldone',ldone
4832       if (MyRank.gt.0) then
4833 C Send correlation contributions to the preceding processor
4834         msglen=msglen1
4835         nn=num_cont_hb(iatel_s)
4836         call pack_buffer(max_cont,max_dim,iatel_s,0,buffer)
4837 cd      write (iout,*) 'The BUFFER array:'
4838 cd      do i=1,nn
4839 cd        write (iout,'(i2,9(3f8.3,2x))') i,(buffer(i,j),j=1,26)
4840 cd      enddo
4841         if (ielstart(iatel_s).gt.iatel_s+ispp) then
4842           msglen=msglen2
4843             call pack_buffer(max_cont,max_dim,iatel_s+1,26,buffer)
4844 C Clear the contacts of the atom passed to the neighboring processor
4845         nn=num_cont_hb(iatel_s+1)
4846 cd      do i=1,nn
4847 cd        write (iout,'(i2,9(3f8.3,2x))') i,(buffer(i,j+26),j=1,26)
4848 cd      enddo
4849             num_cont_hb(iatel_s)=0
4850         endif
4851 cd      write (iout,*) 'Processor ',MyID,MyRank,
4852 cd   & ' is sending correlation contribution to processor',MyID-1,
4853 cd   & ' msglen=',msglen
4854 cd      write (*,*) 'Processor ',MyID,MyRank,
4855 cd   & ' is sending correlation contribution to processor',MyID-1,
4856 cd   & ' msglen=',msglen,' CorrelType=',CorrelType
4857         call mp_bsend(buffer,msglen,MyID-1,CorrelType,CorrelID)
4858 cd      write (iout,*) 'Processor ',MyID,
4859 cd   & ' has sent correlation contribution to processor',MyID-1,
4860 cd   & ' msglen=',msglen,' CorrelID=',CorrelID
4861 cd      write (*,*) 'Processor ',MyID,
4862 cd   & ' has sent correlation contribution to processor',MyID-1,
4863 cd   & ' msglen=',msglen,' CorrelID=',CorrelID
4864         msglen=msglen1
4865       endif ! (MyRank.gt.0)
4866       if (ldone) goto 30
4867       ldone=.true.
4868    20 continue
4869 cd    write (iout,*) 'Receiving: MyRank',MyRank,' mm',mm,' ldone',ldone
4870       if (MyRank.lt.fgProcs-1) then
4871 C Receive correlation contributions from the next processor
4872         msglen=msglen1
4873         if (ielend(iatel_e).lt.nct-1) msglen=msglen2
4874 cd      write (iout,*) 'Processor',MyID,
4875 cd   & ' is receiving correlation contribution from processor',MyID+1,
4876 cd   & ' msglen=',msglen,' CorrelType=',CorrelType
4877 cd      write (*,*) 'Processor',MyID,
4878 cd   & ' is receiving correlation contribution from processor',MyID+1,
4879 cd   & ' msglen=',msglen,' CorrelType=',CorrelType
4880         nbytes=-1
4881         do while (nbytes.le.0)
4882           call mp_probe(MyID+1,CorrelType,nbytes)
4883         enddo
4884 cd      print *,'Processor',MyID,' msglen',msglen,' nbytes',nbytes
4885         call mp_brecv(buffer,msglen,MyID+1,CorrelType,nbytes)
4886 cd      write (iout,*) 'Processor',MyID,
4887 cd   & ' has received correlation contribution from processor',MyID+1,
4888 cd   & ' msglen=',msglen,' nbytes=',nbytes
4889 cd      write (iout,*) 'The received BUFFER array:'
4890 cd      do i=1,max_cont
4891 cd        write (iout,'(i2,9(3f8.3,2x))') i,(buffer(i,j),j=1,52)
4892 cd      enddo
4893         if (msglen.eq.msglen1) then
4894           call unpack_buffer(max_cont,max_dim,iatel_e+1,0,buffer)
4895         else if (msglen.eq.msglen2)  then
4896           call unpack_buffer(max_cont,max_dim,iatel_e,0,buffer)
4897           call unpack_buffer(max_cont,max_dim,iatel_e+1,26,buffer)
4898         else
4899           write (iout,*)
4900      & 'ERROR!!!! message length changed while processing correlations.'
4901           write (*,*)
4902      & 'ERROR!!!! message length changed while processing correlations.'
4903           call mp_stopall(Error)
4904         endif ! msglen.eq.msglen1
4905       endif ! MyRank.lt.fgProcs-1
4906       if (ldone) goto 30
4907       ldone=.true.
4908       goto 10
4909    30 continue
4910 #endif
4911       if (lprn) then
4912         write (iout,'(a)') 'Contact function values:'
4913         do i=nnt,nct-2
4914           write (iout,'(2i3,50(1x,i2,f5.2))')
4915      &    i,num_cont_hb(i),(jcont_hb(j,i),facont_hb(j,i),
4916      &    j=1,num_cont_hb(i))
4917         enddo
4918       endif
4919       ecorr=0.0D0
4920 C Remove the loop below after debugging !!!
4921       do i=nnt,nct
4922         do j=1,3
4923           gradcorr(j,i)=0.0D0
4924           gradxorr(j,i)=0.0D0
4925         enddo
4926       enddo
4927 C Calculate the local-electrostatic correlation terms
4928       do i=iatel_s,iatel_e+1
4929         i1=i+1
4930         num_conti=num_cont_hb(i)
4931         num_conti1=num_cont_hb(i+1)
4932         do jj=1,num_conti
4933           j=jcont_hb(jj,i)
4934           do kk=1,num_conti1
4935             j1=jcont_hb(kk,i1)
4936 c            write (iout,*) 'i=',i,' j=',j,' i1=',i1,' j1=',j1,
4937 c     &         ' jj=',jj,' kk=',kk
4938             if (j1.eq.j+1 .or. j1.eq.j-1) then
4939 C Contacts I-J and (I+1)-(J+1) or (I+1)-(J-1) occur simultaneously.
4940 C The system gains extra energy.
4941               ecorr=ecorr+ehbcorr(i,j,i+1,j1,jj,kk,0.72D0,0.32D0)
4942               n_corr=n_corr+1
4943             else if (j1.eq.j) then
4944 C Contacts I-J and I-(J+1) occur simultaneously.
4945 C The system loses extra energy.
4946 c             ecorr=ecorr+ehbcorr(i,j,i+1,j,jj,kk,0.60D0,-0.40D0)
4947             endif
4948           enddo ! kk
4949           do kk=1,num_conti
4950             j1=jcont_hb(kk,i)
4951 c           write (iout,*) 'i=',i,' j=',j,' i1=',i1,' j1=',j1,
4952 c    &         ' jj=',jj,' kk=',kk
4953             if (j1.eq.j+1) then
4954 C Contacts I-J and (I+1)-J occur simultaneously.
4955 C The system loses extra energy.
4956 c             ecorr=ecorr+ehbcorr(i,j,i,j+1,jj,kk,0.60D0,-0.40D0)
4957             endif ! j1==j+1
4958           enddo ! kk
4959         enddo ! jj
4960       enddo ! i
4961       return
4962       end
4963 c------------------------------------------------------------------------------
4964       subroutine multibody_eello(ecorr,ecorr5,ecorr6,eturn6,n_corr,
4965      &  n_corr1)
4966 C This subroutine calculates multi-body contributions to hydrogen-bonding
4967       implicit real*8 (a-h,o-z)
4968       include 'DIMENSIONS'
4969       include 'DIMENSIONS.ZSCOPT'
4970       include 'COMMON.IOUNITS'
4971 #ifdef MPL
4972       include 'COMMON.INFO'
4973 #endif
4974       include 'COMMON.FFIELD'
4975       include 'COMMON.DERIV'
4976       include 'COMMON.INTERACT'
4977       include 'COMMON.CONTACTS'
4978 #ifdef MPL
4979       parameter (max_cont=maxconts)
4980       parameter (max_dim=2*(8*3+2))
4981       parameter (msglen1=max_cont*max_dim*4)
4982       parameter (msglen2=2*msglen1)
4983       integer source,CorrelType,CorrelID,Error
4984       double precision buffer(max_cont,max_dim)
4985 #endif
4986       double precision gx(3),gx1(3)
4987       logical lprn,ldone
4988
4989 C Set lprn=.true. for debugging
4990       lprn=.false.
4991       eturn6=0.0d0
4992 #ifdef MPL
4993       n_corr=0
4994       n_corr1=0
4995       if (fgProcs.le.1) goto 30
4996       if (lprn) then
4997         write (iout,'(a)') 'Contact function values:'
4998         do i=nnt,nct-2
4999           write (iout,'(2i3,50(1x,i2,f5.2))')
5000      &    i,num_cont_hb(i),(jcont_hb(j,i),facont_hb(j,i),
5001      &    j=1,num_cont_hb(i))
5002         enddo
5003       endif
5004 C Caution! Following code assumes that electrostatic interactions concerning
5005 C a given atom are split among at most two processors!
5006       CorrelType=477
5007       CorrelID=MyID+1
5008       ldone=.false.
5009       do i=1,max_cont
5010         do j=1,max_dim
5011           buffer(i,j)=0.0D0
5012         enddo
5013       enddo
5014       mm=mod(MyRank,2)
5015 cd    write (iout,*) 'MyRank',MyRank,' mm',mm
5016       if (mm) 20,20,10
5017    10 continue
5018 cd    write (iout,*) 'Sending: MyRank',MyRank,' mm',mm,' ldone',ldone
5019       if (MyRank.gt.0) then
5020 C Send correlation contributions to the preceding processor
5021         msglen=msglen1
5022         nn=num_cont_hb(iatel_s)
5023         call pack_buffer(max_cont,max_dim,iatel_s,0,buffer)
5024 cd      write (iout,*) 'The BUFFER array:'
5025 cd      do i=1,nn
5026 cd        write (iout,'(i2,9(3f8.3,2x))') i,(buffer(i,j),j=1,26)
5027 cd      enddo
5028         if (ielstart(iatel_s).gt.iatel_s+ispp) then
5029           msglen=msglen2
5030             call pack_buffer(max_cont,max_dim,iatel_s+1,26,buffer)
5031 C Clear the contacts of the atom passed to the neighboring processor
5032         nn=num_cont_hb(iatel_s+1)
5033 cd      do i=1,nn
5034 cd        write (iout,'(i2,9(3f8.3,2x))') i,(buffer(i,j+26),j=1,26)
5035 cd      enddo
5036             num_cont_hb(iatel_s)=0
5037         endif
5038 cd      write (iout,*) 'Processor ',MyID,MyRank,
5039 cd   & ' is sending correlation contribution to processor',MyID-1,
5040 cd   & ' msglen=',msglen
5041 cd      write (*,*) 'Processor ',MyID,MyRank,
5042 cd   & ' is sending correlation contribution to processor',MyID-1,
5043 cd   & ' msglen=',msglen,' CorrelType=',CorrelType
5044         call mp_bsend(buffer,msglen,MyID-1,CorrelType,CorrelID)
5045 cd      write (iout,*) 'Processor ',MyID,
5046 cd   & ' has sent correlation contribution to processor',MyID-1,
5047 cd   & ' msglen=',msglen,' CorrelID=',CorrelID
5048 cd      write (*,*) 'Processor ',MyID,
5049 cd   & ' has sent correlation contribution to processor',MyID-1,
5050 cd   & ' msglen=',msglen,' CorrelID=',CorrelID
5051         msglen=msglen1
5052       endif ! (MyRank.gt.0)
5053       if (ldone) goto 30
5054       ldone=.true.
5055    20 continue
5056 cd    write (iout,*) 'Receiving: MyRank',MyRank,' mm',mm,' ldone',ldone
5057       if (MyRank.lt.fgProcs-1) then
5058 C Receive correlation contributions from the next processor
5059         msglen=msglen1
5060         if (ielend(iatel_e).lt.nct-1) msglen=msglen2
5061 cd      write (iout,*) 'Processor',MyID,
5062 cd   & ' is receiving correlation contribution from processor',MyID+1,
5063 cd   & ' msglen=',msglen,' CorrelType=',CorrelType
5064 cd      write (*,*) 'Processor',MyID,
5065 cd   & ' is receiving correlation contribution from processor',MyID+1,
5066 cd   & ' msglen=',msglen,' CorrelType=',CorrelType
5067         nbytes=-1
5068         do while (nbytes.le.0)
5069           call mp_probe(MyID+1,CorrelType,nbytes)
5070         enddo
5071 cd      print *,'Processor',MyID,' msglen',msglen,' nbytes',nbytes
5072         call mp_brecv(buffer,msglen,MyID+1,CorrelType,nbytes)
5073 cd      write (iout,*) 'Processor',MyID,
5074 cd   & ' has received correlation contribution from processor',MyID+1,
5075 cd   & ' msglen=',msglen,' nbytes=',nbytes
5076 cd      write (iout,*) 'The received BUFFER array:'
5077 cd      do i=1,max_cont
5078 cd        write (iout,'(i2,9(3f8.3,2x))') i,(buffer(i,j),j=1,52)
5079 cd      enddo
5080         if (msglen.eq.msglen1) then
5081           call unpack_buffer(max_cont,max_dim,iatel_e+1,0,buffer)
5082         else if (msglen.eq.msglen2)  then
5083           call unpack_buffer(max_cont,max_dim,iatel_e,0,buffer)
5084           call unpack_buffer(max_cont,max_dim,iatel_e+1,26,buffer)
5085         else
5086           write (iout,*)
5087      & 'ERROR!!!! message length changed while processing correlations.'
5088           write (*,*)
5089      & 'ERROR!!!! message length changed while processing correlations.'
5090           call mp_stopall(Error)
5091         endif ! msglen.eq.msglen1
5092       endif ! MyRank.lt.fgProcs-1
5093       if (ldone) goto 30
5094       ldone=.true.
5095       goto 10
5096    30 continue
5097 #endif
5098       if (lprn) then
5099         write (iout,'(a)') 'Contact function values:'
5100         do i=nnt,nct-2
5101           write (iout,'(2i3,50(1x,i2,f5.2))')
5102      &    i,num_cont_hb(i),(jcont_hb(j,i),facont_hb(j,i),
5103      &    j=1,num_cont_hb(i))
5104         enddo
5105       endif
5106       ecorr=0.0D0
5107       ecorr5=0.0d0
5108       ecorr6=0.0d0
5109 C Remove the loop below after debugging !!!
5110       do i=nnt,nct
5111         do j=1,3
5112           gradcorr(j,i)=0.0D0
5113           gradxorr(j,i)=0.0D0
5114         enddo
5115       enddo
5116 C Calculate the dipole-dipole interaction energies
5117       if (wcorr6.gt.0.0d0 .or. wturn6.gt.0.0d0) then
5118       do i=iatel_s,iatel_e+1
5119         num_conti=num_cont_hb(i)
5120         do jj=1,num_conti
5121           j=jcont_hb(jj,i)
5122           call dipole(i,j,jj)
5123         enddo
5124       enddo
5125       endif
5126 C Calculate the local-electrostatic correlation terms
5127       do i=iatel_s,iatel_e+1
5128         i1=i+1
5129         num_conti=num_cont_hb(i)
5130         num_conti1=num_cont_hb(i+1)
5131         do jj=1,num_conti
5132           j=jcont_hb(jj,i)
5133           do kk=1,num_conti1
5134             j1=jcont_hb(kk,i1)
5135 c            write (*,*) 'i=',i,' j=',j,' i1=',i1,' j1=',j1,
5136 c     &         ' jj=',jj,' kk=',kk
5137             if (j1.eq.j+1 .or. j1.eq.j-1) then
5138 C Contacts I-J and (I+1)-(J+1) or (I+1)-(J-1) occur simultaneously.
5139 C The system gains extra energy.
5140               n_corr=n_corr+1
5141               sqd1=dsqrt(d_cont(jj,i))
5142               sqd2=dsqrt(d_cont(kk,i1))
5143               sred_geom = sqd1*sqd2
5144               IF (sred_geom.lt.cutoff_corr) THEN
5145                 call gcont(sred_geom,r0_corr,1.0D0,delt_corr,
5146      &            ekont,fprimcont)
5147 c               write (*,*) 'i=',i,' j=',j,' i1=',i1,' j1=',j1,
5148 c     &         ' jj=',jj,' kk=',kk
5149                 fac_prim1=0.5d0*sqd2/sqd1*fprimcont
5150                 fac_prim2=0.5d0*sqd1/sqd2*fprimcont
5151                 do l=1,3
5152                   g_contij(l,1)=fac_prim1*grij_hb_cont(l,jj,i)
5153                   g_contij(l,2)=fac_prim2*grij_hb_cont(l,kk,i1)
5154                 enddo
5155                 n_corr1=n_corr1+1
5156 cd               write (iout,*) 'sred_geom=',sred_geom,
5157 cd     &          ' ekont=',ekont,' fprim=',fprimcont
5158                 call calc_eello(i,j,i+1,j1,jj,kk)
5159                 if (wcorr4.gt.0.0d0)
5160      &            ecorr=ecorr+eello4(i,j,i+1,j1,jj,kk)
5161                 if (wcorr5.gt.0.0d0)
5162      &            ecorr5=ecorr5+eello5(i,j,i+1,j1,jj,kk)
5163 c                print *,"wcorr5",ecorr5
5164 cd                write(2,*)'wcorr6',wcorr6,' wturn6',wturn6
5165 cd                write(2,*)'ijkl',i,j,i+1,j1
5166                 if (wcorr6.gt.0.0d0 .and. (j.ne.i+4 .or. j1.ne.i+3
5167      &               .or. wturn6.eq.0.0d0))then
5168 cd                  write (iout,*) '******ecorr6: i,j,i+1,j1',i,j,i+1,j1
5169                   ecorr6=ecorr6+eello6(i,j,i+1,j1,jj,kk)
5170 cd                write (iout,*) 'ecorr',ecorr,' ecorr5=',ecorr5,
5171 cd     &            'ecorr6=',ecorr6
5172 cd                write (iout,'(4e15.5)') sred_geom,
5173 cd     &          dabs(eello4(i,j,i+1,j1,jj,kk)),
5174 cd     &          dabs(eello5(i,j,i+1,j1,jj,kk)),
5175 cd     &          dabs(eello6(i,j,i+1,j1,jj,kk))
5176                 else if (wturn6.gt.0.0d0
5177      &            .and. (j.eq.i+4 .and. j1.eq.i+3)) then
5178 cd                  write (iout,*) '******eturn6: i,j,i+1,j1',i,j,i+1,j1
5179                   eturn6=eturn6+eello_turn6(i,jj,kk)
5180 cd                  write (2,*) 'multibody_eello:eturn6',eturn6
5181                 endif
5182               ENDIF
5183 1111          continue
5184             else if (j1.eq.j) then
5185 C Contacts I-J and I-(J+1) occur simultaneously.
5186 C The system loses extra energy.
5187 c             ecorr=ecorr+ehbcorr(i,j,i+1,j,jj,kk,0.60D0,-0.40D0)
5188             endif
5189           enddo ! kk
5190           do kk=1,num_conti
5191             j1=jcont_hb(kk,i)
5192 c           write (iout,*) 'i=',i,' j=',j,' i1=',i1,' j1=',j1,
5193 c    &         ' jj=',jj,' kk=',kk
5194             if (j1.eq.j+1) then
5195 C Contacts I-J and (I+1)-J occur simultaneously.
5196 C The system loses extra energy.
5197 c             ecorr=ecorr+ehbcorr(i,j,i,j+1,jj,kk,0.60D0,-0.40D0)
5198             endif ! j1==j+1
5199           enddo ! kk
5200         enddo ! jj
5201       enddo ! i
5202       return
5203       end
5204 c------------------------------------------------------------------------------
5205       double precision function ehbcorr(i,j,k,l,jj,kk,coeffp,coeffm)
5206       implicit real*8 (a-h,o-z)
5207       include 'DIMENSIONS'
5208       include 'COMMON.IOUNITS'
5209       include 'COMMON.DERIV'
5210       include 'COMMON.INTERACT'
5211       include 'COMMON.CONTACTS'
5212       double precision gx(3),gx1(3)
5213       logical lprn
5214       lprn=.false.
5215       eij=facont_hb(jj,i)
5216       ekl=facont_hb(kk,k)
5217       ees0pij=ees0p(jj,i)
5218       ees0pkl=ees0p(kk,k)
5219       ees0mij=ees0m(jj,i)
5220       ees0mkl=ees0m(kk,k)
5221       ekont=eij*ekl
5222       ees=-(coeffp*ees0pij*ees0pkl+coeffm*ees0mij*ees0mkl)
5223 cd    ees=-(coeffp*ees0pkl+coeffm*ees0mkl)
5224 C Following 4 lines for diagnostics.
5225 cd    ees0pkl=0.0D0
5226 cd    ees0pij=1.0D0
5227 cd    ees0mkl=0.0D0
5228 cd    ees0mij=1.0D0
5229 c     write (iout,*)'Contacts have occurred for peptide groups',i,j,
5230 c    &   ' and',k,l
5231 c     write (iout,*)'Contacts have occurred for peptide groups',
5232 c    &  i,j,' fcont:',eij,' eij',' eesij',ees0pij,ees0mij,' and ',k,l
5233 c    & ,' fcont ',ekl,' eeskl',ees0pkl,ees0mkl,' ees=',ees
5234 C Calculate the multi-body contribution to energy.
5235       ecorr=ecorr+ekont*ees
5236       if (calc_grad) then
5237 C Calculate multi-body contributions to the gradient.
5238       do ll=1,3
5239         ghalf=0.5D0*ees*ekl*gacont_hbr(ll,jj,i)
5240         gradcorr(ll,i)=gradcorr(ll,i)+ghalf
5241      &  -ekont*(coeffp*ees0pkl*gacontp_hb1(ll,jj,i)+
5242      &  coeffm*ees0mkl*gacontm_hb1(ll,jj,i))
5243         gradcorr(ll,j)=gradcorr(ll,j)+ghalf
5244      &  -ekont*(coeffp*ees0pkl*gacontp_hb2(ll,jj,i)+
5245      &  coeffm*ees0mkl*gacontm_hb2(ll,jj,i))
5246         ghalf=0.5D0*ees*eij*gacont_hbr(ll,kk,k)
5247         gradcorr(ll,k)=gradcorr(ll,k)+ghalf
5248      &  -ekont*(coeffp*ees0pij*gacontp_hb1(ll,kk,k)+
5249      &  coeffm*ees0mij*gacontm_hb1(ll,kk,k))
5250         gradcorr(ll,l)=gradcorr(ll,l)+ghalf
5251      &  -ekont*(coeffp*ees0pij*gacontp_hb2(ll,kk,k)+
5252      &  coeffm*ees0mij*gacontm_hb2(ll,kk,k))
5253       enddo
5254       do m=i+1,j-1
5255         do ll=1,3
5256           gradcorr(ll,m)=gradcorr(ll,m)+
5257      &     ees*ekl*gacont_hbr(ll,jj,i)-
5258      &     ekont*(coeffp*ees0pkl*gacontp_hb3(ll,jj,i)+
5259      &     coeffm*ees0mkl*gacontm_hb3(ll,jj,i))
5260         enddo
5261       enddo
5262       do m=k+1,l-1
5263         do ll=1,3
5264           gradcorr(ll,m)=gradcorr(ll,m)+
5265      &     ees*eij*gacont_hbr(ll,kk,k)-
5266      &     ekont*(coeffp*ees0pij*gacontp_hb3(ll,kk,k)+
5267      &     coeffm*ees0mij*gacontm_hb3(ll,kk,k))
5268         enddo
5269       enddo
5270       endif
5271       ehbcorr=ekont*ees
5272       return
5273       end
5274 C---------------------------------------------------------------------------
5275       subroutine dipole(i,j,jj)
5276       implicit real*8 (a-h,o-z)
5277       include 'DIMENSIONS'
5278       include 'DIMENSIONS.ZSCOPT'
5279       include 'COMMON.IOUNITS'
5280       include 'COMMON.CHAIN'
5281       include 'COMMON.FFIELD'
5282       include 'COMMON.DERIV'
5283       include 'COMMON.INTERACT'
5284       include 'COMMON.CONTACTS'
5285       include 'COMMON.TORSION'
5286       include 'COMMON.VAR'
5287       include 'COMMON.GEO'
5288       dimension dipi(2,2),dipj(2,2),dipderi(2),dipderj(2),auxvec(2),
5289      &  auxmat(2,2)
5290       iti1 = itortyp(itype(i+1))
5291       if (j.lt.nres-1) then
5292         itj1 = itortyp(itype(j+1))
5293       else
5294         itj1=ntortyp+1
5295       endif
5296       do iii=1,2
5297         dipi(iii,1)=Ub2(iii,i)
5298         dipderi(iii)=Ub2der(iii,i)
5299         dipi(iii,2)=b1(iii,iti1)
5300         dipj(iii,1)=Ub2(iii,j)
5301         dipderj(iii)=Ub2der(iii,j)
5302         dipj(iii,2)=b1(iii,itj1)
5303       enddo
5304       kkk=0
5305       do iii=1,2
5306         call matvec2(a_chuj(1,1,jj,i),dipj(1,iii),auxvec(1))
5307         do jjj=1,2
5308           kkk=kkk+1
5309           dip(kkk,jj,i)=scalar2(dipi(1,jjj),auxvec(1))
5310         enddo
5311       enddo
5312       if (.not.calc_grad) return
5313       do kkk=1,5
5314         do lll=1,3
5315           mmm=0
5316           do iii=1,2
5317             call matvec2(a_chuj_der(1,1,lll,kkk,jj,i),dipj(1,iii),
5318      &        auxvec(1))
5319             do jjj=1,2
5320               mmm=mmm+1
5321               dipderx(lll,kkk,mmm,jj,i)=scalar2(dipi(1,jjj),auxvec(1))
5322             enddo
5323           enddo
5324         enddo
5325       enddo
5326       call transpose2(a_chuj(1,1,jj,i),auxmat(1,1))
5327       call matvec2(auxmat(1,1),dipderi(1),auxvec(1))
5328       do iii=1,2
5329         dipderg(iii,jj,i)=scalar2(auxvec(1),dipj(1,iii))
5330       enddo
5331       call matvec2(a_chuj(1,1,jj,i),dipderj(1),auxvec(1))
5332       do iii=1,2
5333         dipderg(iii+2,jj,i)=scalar2(auxvec(1),dipi(1,iii))
5334       enddo
5335       return
5336       end
5337 C---------------------------------------------------------------------------
5338       subroutine calc_eello(i,j,k,l,jj,kk)
5339 C
5340 C This subroutine computes matrices and vectors needed to calculate
5341 C the fourth-, fifth-, and sixth-order local-electrostatic terms.
5342 C
5343       implicit real*8 (a-h,o-z)
5344       include 'DIMENSIONS'
5345       include 'DIMENSIONS.ZSCOPT'
5346       include 'COMMON.IOUNITS'
5347       include 'COMMON.CHAIN'
5348       include 'COMMON.DERIV'
5349       include 'COMMON.INTERACT'
5350       include 'COMMON.CONTACTS'
5351       include 'COMMON.TORSION'
5352       include 'COMMON.VAR'
5353       include 'COMMON.GEO'
5354       include 'COMMON.FFIELD'
5355       double precision aa1(2,2),aa2(2,2),aa1t(2,2),aa2t(2,2),
5356      &  aa1tder(2,2,3,5),aa2tder(2,2,3,5),auxmat(2,2)
5357       logical lprn
5358       common /kutas/ lprn
5359 cd      write (iout,*) 'calc_eello: i=',i,' j=',j,' k=',k,' l=',l,
5360 cd     & ' jj=',jj,' kk=',kk
5361 cd      if (i.ne.2 .or. j.ne.4 .or. k.ne.3 .or. l.ne.5) return
5362       do iii=1,2
5363         do jjj=1,2
5364           aa1(iii,jjj)=a_chuj(iii,jjj,jj,i)
5365           aa2(iii,jjj)=a_chuj(iii,jjj,kk,k)
5366         enddo
5367       enddo
5368       call transpose2(aa1(1,1),aa1t(1,1))
5369       call transpose2(aa2(1,1),aa2t(1,1))
5370       do kkk=1,5
5371         do lll=1,3
5372           call transpose2(a_chuj_der(1,1,lll,kkk,jj,i),
5373      &      aa1tder(1,1,lll,kkk))
5374           call transpose2(a_chuj_der(1,1,lll,kkk,kk,k),
5375      &      aa2tder(1,1,lll,kkk))
5376         enddo
5377       enddo
5378       if (l.eq.j+1) then
5379 C parallel orientation of the two CA-CA-CA frames.
5380         if (i.gt.1) then
5381           iti=itortyp(itype(i))
5382         else
5383           iti=ntortyp+1
5384         endif
5385         itk1=itortyp(itype(k+1))
5386         itj=itortyp(itype(j))
5387         if (l.lt.nres-1) then
5388           itl1=itortyp(itype(l+1))
5389         else
5390           itl1=ntortyp+1
5391         endif
5392 C A1 kernel(j+1) A2T
5393 cd        do iii=1,2
5394 cd          write (iout,'(3f10.5,5x,3f10.5)')
5395 cd     &     (EUg(iii,jjj,k),jjj=1,2),(EUg(iii,jjj,l),jjj=1,2)
5396 cd        enddo
5397         call kernel(aa1(1,1),aa2t(1,1),a_chuj_der(1,1,1,1,jj,i),
5398      &   aa2tder(1,1,1,1),1,.false.,EUg(1,1,l),EUgder(1,1,l),
5399      &   AEA(1,1,1),AEAderg(1,1,1),AEAderx(1,1,1,1,1,1))
5400 C Following matrices are needed only for 6-th order cumulants
5401         IF (wcorr6.gt.0.0d0) THEN
5402         call kernel(aa1(1,1),aa2t(1,1),a_chuj_der(1,1,1,1,jj,i),
5403      &   aa2tder(1,1,1,1),1,.false.,EUgC(1,1,l),EUgCder(1,1,l),
5404      &   AECA(1,1,1),AECAderg(1,1,1),AECAderx(1,1,1,1,1,1))
5405         call kernel(aa1(1,1),aa2t(1,1),a_chuj_der(1,1,1,1,jj,i),
5406      &   aa2tder(1,1,1,1),2,.false.,Ug2DtEUg(1,1,l),
5407      &   Ug2DtEUgder(1,1,1,l),ADtEA(1,1,1),ADtEAderg(1,1,1,1),
5408      &   ADtEAderx(1,1,1,1,1,1))
5409         lprn=.false.
5410         call kernel(aa1(1,1),aa2t(1,1),a_chuj_der(1,1,1,1,jj,i),
5411      &   aa2tder(1,1,1,1),2,.false.,DtUg2EUg(1,1,l),
5412      &   DtUg2EUgder(1,1,1,l),ADtEA1(1,1,1),ADtEA1derg(1,1,1,1),
5413      &   ADtEA1derx(1,1,1,1,1,1))
5414         ENDIF
5415 C End 6-th order cumulants
5416 cd        lprn=.false.
5417 cd        if (lprn) then
5418 cd        write (2,*) 'In calc_eello6'
5419 cd        do iii=1,2
5420 cd          write (2,*) 'iii=',iii
5421 cd          do kkk=1,5
5422 cd            write (2,*) 'kkk=',kkk
5423 cd            do jjj=1,2
5424 cd              write (2,'(3(2f10.5),5x)')
5425 cd     &        ((ADtEA1derx(jjj,mmm,lll,kkk,iii,1),mmm=1,2),lll=1,3)
5426 cd            enddo
5427 cd          enddo
5428 cd        enddo
5429 cd        endif
5430         call transpose2(EUgder(1,1,k),auxmat(1,1))
5431         call matmat2(auxmat(1,1),AEA(1,1,1),EAEAderg(1,1,1,1))
5432         call transpose2(EUg(1,1,k),auxmat(1,1))
5433         call matmat2(auxmat(1,1),AEA(1,1,1),EAEA(1,1,1))
5434         call matmat2(auxmat(1,1),AEAderg(1,1,1),EAEAderg(1,1,2,1))
5435         do iii=1,2
5436           do kkk=1,5
5437             do lll=1,3
5438               call matmat2(auxmat(1,1),AEAderx(1,1,lll,kkk,iii,1),
5439      &          EAEAderx(1,1,lll,kkk,iii,1))
5440             enddo
5441           enddo
5442         enddo
5443 C A1T kernel(i+1) A2
5444         call kernel(aa1t(1,1),aa2(1,1),aa1tder(1,1,1,1),
5445      &   a_chuj_der(1,1,1,1,kk,k),1,.false.,EUg(1,1,k),EUgder(1,1,k),
5446      &   AEA(1,1,2),AEAderg(1,1,2),AEAderx(1,1,1,1,1,2))
5447 C Following matrices are needed only for 6-th order cumulants
5448         IF (wcorr6.gt.0.0d0) THEN
5449         call kernel(aa1t(1,1),aa2(1,1),aa1tder(1,1,1,1),
5450      &   a_chuj_der(1,1,1,1,kk,k),1,.false.,EUgC(1,1,k),EUgCder(1,1,k),
5451      &   AECA(1,1,2),AECAderg(1,1,2),AECAderx(1,1,1,1,1,2))
5452         call kernel(aa1t(1,1),aa2(1,1),aa1tder(1,1,1,1),
5453      &   a_chuj_der(1,1,1,1,kk,k),2,.false.,Ug2DtEUg(1,1,k),
5454      &   Ug2DtEUgder(1,1,1,k),ADtEA(1,1,2),ADtEAderg(1,1,1,2),
5455      &   ADtEAderx(1,1,1,1,1,2))
5456         call kernel(aa1t(1,1),aa2(1,1),aa1tder(1,1,1,1),
5457      &   a_chuj_der(1,1,1,1,kk,k),2,.false.,DtUg2EUg(1,1,k),
5458      &   DtUg2EUgder(1,1,1,k),ADtEA1(1,1,2),ADtEA1derg(1,1,1,2),
5459      &   ADtEA1derx(1,1,1,1,1,2))
5460         ENDIF
5461 C End 6-th order cumulants
5462         call transpose2(EUgder(1,1,l),auxmat(1,1))
5463         call matmat2(auxmat(1,1),AEA(1,1,2),EAEAderg(1,1,1,2))
5464         call transpose2(EUg(1,1,l),auxmat(1,1))
5465         call matmat2(auxmat(1,1),AEA(1,1,2),EAEA(1,1,2))
5466         call matmat2(auxmat(1,1),AEAderg(1,1,2),EAEAderg(1,1,2,2))
5467         do iii=1,2
5468           do kkk=1,5
5469             do lll=1,3
5470               call matmat2(auxmat(1,1),AEAderx(1,1,lll,kkk,iii,2),
5471      &          EAEAderx(1,1,lll,kkk,iii,2))
5472             enddo
5473           enddo
5474         enddo
5475 C AEAb1 and AEAb2
5476 C Calculate the vectors and their derivatives in virtual-bond dihedral angles.
5477 C They are needed only when the fifth- or the sixth-order cumulants are
5478 C indluded.
5479         IF (wcorr5.gt.0.0d0 .or. wcorr6.gt.0.0d0) THEN
5480         call transpose2(AEA(1,1,1),auxmat(1,1))
5481         call matvec2(auxmat(1,1),b1(1,iti),AEAb1(1,1,1))
5482         call matvec2(auxmat(1,1),Ub2(1,i),AEAb2(1,1,1))
5483         call matvec2(auxmat(1,1),Ub2der(1,i),AEAb2derg(1,2,1,1))
5484         call transpose2(AEAderg(1,1,1),auxmat(1,1))
5485         call matvec2(auxmat(1,1),b1(1,iti),AEAb1derg(1,1,1))
5486         call matvec2(auxmat(1,1),Ub2(1,i),AEAb2derg(1,1,1,1))
5487         call matvec2(AEA(1,1,1),b1(1,itk1),AEAb1(1,2,1))
5488         call matvec2(AEAderg(1,1,1),b1(1,itk1),AEAb1derg(1,2,1))
5489         call matvec2(AEA(1,1,1),Ub2(1,k+1),AEAb2(1,2,1))
5490         call matvec2(AEAderg(1,1,1),Ub2(1,k+1),AEAb2derg(1,1,2,1))
5491         call matvec2(AEA(1,1,1),Ub2der(1,k+1),AEAb2derg(1,2,2,1))
5492         call transpose2(AEA(1,1,2),auxmat(1,1))
5493         call matvec2(auxmat(1,1),b1(1,itj),AEAb1(1,1,2))
5494         call matvec2(auxmat(1,1),Ub2(1,j),AEAb2(1,1,2))
5495         call matvec2(auxmat(1,1),Ub2der(1,j),AEAb2derg(1,2,1,2))
5496         call transpose2(AEAderg(1,1,2),auxmat(1,1))
5497         call matvec2(auxmat(1,1),b1(1,itj),AEAb1derg(1,1,2))
5498         call matvec2(auxmat(1,1),Ub2(1,j),AEAb2derg(1,1,1,2))
5499         call matvec2(AEA(1,1,2),b1(1,itl1),AEAb1(1,2,2))
5500         call matvec2(AEAderg(1,1,2),b1(1,itl1),AEAb1derg(1,2,2))
5501         call matvec2(AEA(1,1,2),Ub2(1,l+1),AEAb2(1,2,2))
5502         call matvec2(AEAderg(1,1,2),Ub2(1,l+1),AEAb2derg(1,1,2,2))
5503         call matvec2(AEA(1,1,2),Ub2der(1,l+1),AEAb2derg(1,2,2,2))
5504 C Calculate the Cartesian derivatives of the vectors.
5505         do iii=1,2
5506           do kkk=1,5
5507             do lll=1,3
5508               call transpose2(AEAderx(1,1,lll,kkk,iii,1),auxmat(1,1))
5509               call matvec2(auxmat(1,1),b1(1,iti),
5510      &          AEAb1derx(1,lll,kkk,iii,1,1))
5511               call matvec2(auxmat(1,1),Ub2(1,i),
5512      &          AEAb2derx(1,lll,kkk,iii,1,1))
5513               call matvec2(AEAderx(1,1,lll,kkk,iii,1),b1(1,itk1),
5514      &          AEAb1derx(1,lll,kkk,iii,2,1))
5515               call matvec2(AEAderx(1,1,lll,kkk,iii,1),Ub2(1,k+1),
5516      &          AEAb2derx(1,lll,kkk,iii,2,1))
5517               call transpose2(AEAderx(1,1,lll,kkk,iii,2),auxmat(1,1))
5518               call matvec2(auxmat(1,1),b1(1,itj),
5519      &          AEAb1derx(1,lll,kkk,iii,1,2))
5520               call matvec2(auxmat(1,1),Ub2(1,j),
5521      &          AEAb2derx(1,lll,kkk,iii,1,2))
5522               call matvec2(AEAderx(1,1,lll,kkk,iii,2),b1(1,itl1),
5523      &          AEAb1derx(1,lll,kkk,iii,2,2))
5524               call matvec2(AEAderx(1,1,lll,kkk,iii,2),Ub2(1,l+1),
5525      &          AEAb2derx(1,lll,kkk,iii,2,2))
5526             enddo
5527           enddo
5528         enddo
5529         ENDIF
5530 C End vectors
5531       else
5532 C Antiparallel orientation of the two CA-CA-CA frames.
5533         if (i.gt.1) then
5534           iti=itortyp(itype(i))
5535         else
5536           iti=ntortyp+1
5537         endif
5538         itk1=itortyp(itype(k+1))
5539         itl=itortyp(itype(l))
5540         itj=itortyp(itype(j))
5541         if (j.lt.nres-1) then
5542           itj1=itortyp(itype(j+1))
5543         else
5544           itj1=ntortyp+1
5545         endif
5546 C A2 kernel(j-1)T A1T
5547         call kernel(aa1(1,1),aa2t(1,1),a_chuj_der(1,1,1,1,jj,i),
5548      &   aa2tder(1,1,1,1),1,.true.,EUg(1,1,j),EUgder(1,1,j),
5549      &   AEA(1,1,1),AEAderg(1,1,1),AEAderx(1,1,1,1,1,1))
5550 C Following matrices are needed only for 6-th order cumulants
5551         IF (wcorr6.gt.0.0d0 .or. (wturn6.gt.0.0d0 .and.
5552      &     j.eq.i+4 .and. l.eq.i+3)) THEN
5553         call kernel(aa1(1,1),aa2t(1,1),a_chuj_der(1,1,1,1,jj,i),
5554      &   aa2tder(1,1,1,1),1,.true.,EUgC(1,1,j),EUgCder(1,1,j),
5555      &   AECA(1,1,1),AECAderg(1,1,1),AECAderx(1,1,1,1,1,1))
5556         call kernel(aa2(1,1),aa2t(1,1),a_chuj_der(1,1,1,1,jj,i),
5557      &   aa2tder(1,1,1,1),2,.true.,Ug2DtEUg(1,1,j),
5558      &   Ug2DtEUgder(1,1,1,j),ADtEA(1,1,1),ADtEAderg(1,1,1,1),
5559      &   ADtEAderx(1,1,1,1,1,1))
5560         call kernel(aa1(1,1),aa2t(1,1),a_chuj_der(1,1,1,1,jj,i),
5561      &   aa2tder(1,1,1,1),2,.true.,DtUg2EUg(1,1,j),
5562      &   DtUg2EUgder(1,1,1,j),ADtEA1(1,1,1),ADtEA1derg(1,1,1,1),
5563      &   ADtEA1derx(1,1,1,1,1,1))
5564         ENDIF
5565 C End 6-th order cumulants
5566         call transpose2(EUgder(1,1,k),auxmat(1,1))
5567         call matmat2(auxmat(1,1),AEA(1,1,1),EAEAderg(1,1,1,1))
5568         call transpose2(EUg(1,1,k),auxmat(1,1))
5569         call matmat2(auxmat(1,1),AEA(1,1,1),EAEA(1,1,1))
5570         call matmat2(auxmat(1,1),AEAderg(1,1,1),EAEAderg(1,1,2,1))
5571         do iii=1,2
5572           do kkk=1,5
5573             do lll=1,3
5574               call matmat2(auxmat(1,1),AEAderx(1,1,lll,kkk,iii,1),
5575      &          EAEAderx(1,1,lll,kkk,iii,1))
5576             enddo
5577           enddo
5578         enddo
5579 C A2T kernel(i+1)T A1
5580         call kernel(aa2t(1,1),aa1(1,1),aa2tder(1,1,1,1),
5581      &   a_chuj_der(1,1,1,1,jj,i),1,.true.,EUg(1,1,k),EUgder(1,1,k),
5582      &   AEA(1,1,2),AEAderg(1,1,2),AEAderx(1,1,1,1,1,2))
5583 C Following matrices are needed only for 6-th order cumulants
5584         IF (wcorr6.gt.0.0d0 .or. (wturn6.gt.0.0d0 .and.
5585      &     j.eq.i+4 .and. l.eq.i+3)) THEN
5586         call kernel(aa2t(1,1),aa1(1,1),aa2tder(1,1,1,1),
5587      &   a_chuj_der(1,1,1,1,jj,i),1,.true.,EUgC(1,1,k),EUgCder(1,1,k),
5588      &   AECA(1,1,2),AECAderg(1,1,2),AECAderx(1,1,1,1,1,2))
5589         call kernel(aa2t(1,1),aa1(1,1),aa2tder(1,1,1,1),
5590      &   a_chuj_der(1,1,1,1,jj,i),2,.true.,Ug2DtEUg(1,1,k),
5591      &   Ug2DtEUgder(1,1,1,k),ADtEA(1,1,2),ADtEAderg(1,1,1,2),
5592      &   ADtEAderx(1,1,1,1,1,2))
5593         call kernel(aa2t(1,1),aa1(1,1),aa2tder(1,1,1,1),
5594      &   a_chuj_der(1,1,1,1,jj,i),2,.true.,DtUg2EUg(1,1,k),
5595      &   DtUg2EUgder(1,1,1,k),ADtEA1(1,1,2),ADtEA1derg(1,1,1,2),
5596      &   ADtEA1derx(1,1,1,1,1,2))
5597         ENDIF
5598 C End 6-th order cumulants
5599         call transpose2(EUgder(1,1,j),auxmat(1,1))
5600         call matmat2(auxmat(1,1),AEA(1,1,1),EAEAderg(1,1,2,2))
5601         call transpose2(EUg(1,1,j),auxmat(1,1))
5602         call matmat2(auxmat(1,1),AEA(1,1,2),EAEA(1,1,2))
5603         call matmat2(auxmat(1,1),AEAderg(1,1,2),EAEAderg(1,1,2,2))
5604         do iii=1,2
5605           do kkk=1,5
5606             do lll=1,3
5607               call matmat2(auxmat(1,1),AEAderx(1,1,lll,kkk,iii,2),
5608      &          EAEAderx(1,1,lll,kkk,iii,2))
5609             enddo
5610           enddo
5611         enddo
5612 C AEAb1 and AEAb2
5613 C Calculate the vectors and their derivatives in virtual-bond dihedral angles.
5614 C They are needed only when the fifth- or the sixth-order cumulants are
5615 C indluded.
5616         IF (wcorr5.gt.0.0d0 .or. wcorr6.gt.0.0d0 .or.
5617      &    (wturn6.gt.0.0d0 .and. j.eq.i+4 .and. l.eq.i+3)) THEN
5618         call transpose2(AEA(1,1,1),auxmat(1,1))
5619         call matvec2(auxmat(1,1),b1(1,iti),AEAb1(1,1,1))
5620         call matvec2(auxmat(1,1),Ub2(1,i),AEAb2(1,1,1))
5621         call matvec2(auxmat(1,1),Ub2der(1,i),AEAb2derg(1,2,1,1))
5622         call transpose2(AEAderg(1,1,1),auxmat(1,1))
5623         call matvec2(auxmat(1,1),b1(1,iti),AEAb1derg(1,1,1))
5624         call matvec2(auxmat(1,1),Ub2(1,i),AEAb2derg(1,1,1,1))
5625         call matvec2(AEA(1,1,1),b1(1,itk1),AEAb1(1,2,1))
5626         call matvec2(AEAderg(1,1,1),b1(1,itk1),AEAb1derg(1,2,1))
5627         call matvec2(AEA(1,1,1),Ub2(1,k+1),AEAb2(1,2,1))
5628         call matvec2(AEAderg(1,1,1),Ub2(1,k+1),AEAb2derg(1,1,2,1))
5629         call matvec2(AEA(1,1,1),Ub2der(1,k+1),AEAb2derg(1,2,2,1))
5630         call transpose2(AEA(1,1,2),auxmat(1,1))
5631         call matvec2(auxmat(1,1),b1(1,itj1),AEAb1(1,1,2))
5632         call matvec2(auxmat(1,1),Ub2(1,l),AEAb2(1,1,2))
5633         call matvec2(auxmat(1,1),Ub2der(1,l),AEAb2derg(1,2,1,2))
5634         call transpose2(AEAderg(1,1,2),auxmat(1,1))
5635         call matvec2(auxmat(1,1),b1(1,itl),AEAb1(1,1,2))
5636         call matvec2(auxmat(1,1),Ub2(1,l),AEAb2derg(1,1,1,2))
5637         call matvec2(AEA(1,1,2),b1(1,itj1),AEAb1(1,2,2))
5638         call matvec2(AEAderg(1,1,2),b1(1,itj1),AEAb1derg(1,2,2))
5639         call matvec2(AEA(1,1,2),Ub2(1,j),AEAb2(1,2,2))
5640         call matvec2(AEAderg(1,1,2),Ub2(1,j),AEAb2derg(1,1,2,2))
5641         call matvec2(AEA(1,1,2),Ub2der(1,j),AEAb2derg(1,2,2,2))
5642 C Calculate the Cartesian derivatives of the vectors.
5643         do iii=1,2
5644           do kkk=1,5
5645             do lll=1,3
5646               call transpose2(AEAderx(1,1,lll,kkk,iii,1),auxmat(1,1))
5647               call matvec2(auxmat(1,1),b1(1,iti),
5648      &          AEAb1derx(1,lll,kkk,iii,1,1))
5649               call matvec2(auxmat(1,1),Ub2(1,i),
5650      &          AEAb2derx(1,lll,kkk,iii,1,1))
5651               call matvec2(AEAderx(1,1,lll,kkk,iii,1),b1(1,itk1),
5652      &          AEAb1derx(1,lll,kkk,iii,2,1))
5653               call matvec2(AEAderx(1,1,lll,kkk,iii,1),Ub2(1,k+1),
5654      &          AEAb2derx(1,lll,kkk,iii,2,1))
5655               call transpose2(AEAderx(1,1,lll,kkk,iii,2),auxmat(1,1))
5656               call matvec2(auxmat(1,1),b1(1,itl),
5657      &          AEAb1derx(1,lll,kkk,iii,1,2))
5658               call matvec2(auxmat(1,1),Ub2(1,l),
5659      &          AEAb2derx(1,lll,kkk,iii,1,2))
5660               call matvec2(AEAderx(1,1,lll,kkk,iii,2),b1(1,itj1),
5661      &          AEAb1derx(1,lll,kkk,iii,2,2))
5662               call matvec2(AEAderx(1,1,lll,kkk,iii,2),Ub2(1,j),
5663      &          AEAb2derx(1,lll,kkk,iii,2,2))
5664             enddo
5665           enddo
5666         enddo
5667         ENDIF
5668 C End vectors
5669       endif
5670       return
5671       end
5672 C---------------------------------------------------------------------------
5673       subroutine kernel(aa1,aa2t,aa1derx,aa2tderx,nderg,transp,
5674      &  KK,KKderg,AKA,AKAderg,AKAderx)
5675       implicit none
5676       integer nderg
5677       logical transp
5678       double precision aa1(2,2),aa2t(2,2),aa1derx(2,2,3,5),
5679      &  aa2tderx(2,2,3,5),KK(2,2),KKderg(2,2,nderg),AKA(2,2),
5680      &  AKAderg(2,2,nderg),AKAderx(2,2,3,5,2)
5681       integer iii,kkk,lll
5682       integer jjj,mmm
5683       logical lprn
5684       common /kutas/ lprn
5685       call prodmat3(aa1(1,1),aa2t(1,1),KK(1,1),transp,AKA(1,1))
5686       do iii=1,nderg
5687         call prodmat3(aa1(1,1),aa2t(1,1),KKderg(1,1,iii),transp,
5688      &    AKAderg(1,1,iii))
5689       enddo
5690 cd      if (lprn) write (2,*) 'In kernel'
5691       do kkk=1,5
5692 cd        if (lprn) write (2,*) 'kkk=',kkk
5693         do lll=1,3
5694           call prodmat3(aa1derx(1,1,lll,kkk),aa2t(1,1),
5695      &      KK(1,1),transp,AKAderx(1,1,lll,kkk,1))
5696 cd          if (lprn) then
5697 cd            write (2,*) 'lll=',lll
5698 cd            write (2,*) 'iii=1'
5699 cd            do jjj=1,2
5700 cd              write (2,'(3(2f10.5),5x)')
5701 cd     &        (AKAderx(jjj,mmm,lll,kkk,1),mmm=1,2)
5702 cd            enddo
5703 cd          endif
5704           call prodmat3(aa1(1,1),aa2tderx(1,1,lll,kkk),
5705      &      KK(1,1),transp,AKAderx(1,1,lll,kkk,2))
5706 cd          if (lprn) then
5707 cd            write (2,*) 'lll=',lll
5708 cd            write (2,*) 'iii=2'
5709 cd            do jjj=1,2
5710 cd              write (2,'(3(2f10.5),5x)')
5711 cd     &        (AKAderx(jjj,mmm,lll,kkk,2),mmm=1,2)
5712 cd            enddo
5713 cd          endif
5714         enddo
5715       enddo
5716       return
5717       end
5718 C---------------------------------------------------------------------------
5719       double precision function eello4(i,j,k,l,jj,kk)
5720       implicit real*8 (a-h,o-z)
5721       include 'DIMENSIONS'
5722       include 'DIMENSIONS.ZSCOPT'
5723       include 'COMMON.IOUNITS'
5724       include 'COMMON.CHAIN'
5725       include 'COMMON.DERIV'
5726       include 'COMMON.INTERACT'
5727       include 'COMMON.CONTACTS'
5728       include 'COMMON.TORSION'
5729       include 'COMMON.VAR'
5730       include 'COMMON.GEO'
5731       double precision pizda(2,2),ggg1(3),ggg2(3)
5732 cd      if (i.ne.1 .or. j.ne.5 .or. k.ne.2 .or.l.ne.4) then
5733 cd        eello4=0.0d0
5734 cd        return
5735 cd      endif
5736 cd      print *,'eello4:',i,j,k,l,jj,kk
5737 cd      write (2,*) 'i',i,' j',j,' k',k,' l',l
5738 cd      call checkint4(i,j,k,l,jj,kk,eel4_num)
5739 cold      eij=facont_hb(jj,i)
5740 cold      ekl=facont_hb(kk,k)
5741 cold      ekont=eij*ekl
5742       eel4=-EAEA(1,1,1)-EAEA(2,2,1)
5743       if (calc_grad) then
5744 cd      eel41=-EAEA(1,1,2)-EAEA(2,2,2)
5745       gcorr_loc(k-1)=gcorr_loc(k-1)
5746      &   -ekont*(EAEAderg(1,1,1,1)+EAEAderg(2,2,1,1))
5747       if (l.eq.j+1) then
5748         gcorr_loc(l-1)=gcorr_loc(l-1)
5749      &     -ekont*(EAEAderg(1,1,2,1)+EAEAderg(2,2,2,1))
5750       else
5751         gcorr_loc(j-1)=gcorr_loc(j-1)
5752      &     -ekont*(EAEAderg(1,1,2,1)+EAEAderg(2,2,2,1))
5753       endif
5754       do iii=1,2
5755         do kkk=1,5
5756           do lll=1,3
5757             derx(lll,kkk,iii)=-EAEAderx(1,1,lll,kkk,iii,1)
5758      &                        -EAEAderx(2,2,lll,kkk,iii,1)
5759 cd            derx(lll,kkk,iii)=0.0d0
5760           enddo
5761         enddo
5762       enddo
5763 cd      gcorr_loc(l-1)=0.0d0
5764 cd      gcorr_loc(j-1)=0.0d0
5765 cd      gcorr_loc(k-1)=0.0d0
5766 cd      eel4=1.0d0
5767 cd      write (iout,*)'Contacts have occurred for peptide groups',
5768 cd     &  i,j,' fcont:',eij,' eij',' and ',k,l,
5769 cd     &  ' fcont ',ekl,' eel4=',eel4,' eel4_num',16*eel4_num
5770       if (j.lt.nres-1) then
5771         j1=j+1
5772         j2=j-1
5773       else
5774         j1=j-1
5775         j2=j-2
5776       endif
5777       if (l.lt.nres-1) then
5778         l1=l+1
5779         l2=l-1
5780       else
5781         l1=l-1
5782         l2=l-2
5783       endif
5784       do ll=1,3
5785 cold        ghalf=0.5d0*eel4*ekl*gacont_hbr(ll,jj,i)
5786         ggg1(ll)=eel4*g_contij(ll,1)
5787         ggg2(ll)=eel4*g_contij(ll,2)
5788         ghalf=0.5d0*ggg1(ll)
5789 cd        ghalf=0.0d0
5790         gradcorr(ll,i)=gradcorr(ll,i)+ghalf+ekont*derx(ll,2,1)
5791         gradcorr(ll,i+1)=gradcorr(ll,i+1)+ekont*derx(ll,3,1)
5792         gradcorr(ll,j)=gradcorr(ll,j)+ghalf+ekont*derx(ll,4,1)
5793         gradcorr(ll,j1)=gradcorr(ll,j1)+ekont*derx(ll,5,1)
5794 cold        ghalf=0.5d0*eel4*eij*gacont_hbr(ll,kk,k)
5795         ghalf=0.5d0*ggg2(ll)
5796 cd        ghalf=0.0d0
5797         gradcorr(ll,k)=gradcorr(ll,k)+ghalf+ekont*derx(ll,2,2)
5798         gradcorr(ll,k+1)=gradcorr(ll,k+1)+ekont*derx(ll,3,2)
5799         gradcorr(ll,l)=gradcorr(ll,l)+ghalf+ekont*derx(ll,4,2)
5800         gradcorr(ll,l1)=gradcorr(ll,l1)+ekont*derx(ll,5,2)
5801       enddo
5802 cd      goto 1112
5803       do m=i+1,j-1
5804         do ll=1,3
5805 cold          gradcorr(ll,m)=gradcorr(ll,m)+eel4*ekl*gacont_hbr(ll,jj,i)
5806           gradcorr(ll,m)=gradcorr(ll,m)+ggg1(ll)
5807         enddo
5808       enddo
5809       do m=k+1,l-1
5810         do ll=1,3
5811 cold          gradcorr(ll,m)=gradcorr(ll,m)+eel4*eij*gacont_hbr(ll,kk,k)
5812           gradcorr(ll,m)=gradcorr(ll,m)+ggg2(ll)
5813         enddo
5814       enddo
5815 1112  continue
5816       do m=i+2,j2
5817         do ll=1,3
5818           gradcorr(ll,m)=gradcorr(ll,m)+ekont*derx(ll,1,1)
5819         enddo
5820       enddo
5821       do m=k+2,l2
5822         do ll=1,3
5823           gradcorr(ll,m)=gradcorr(ll,m)+ekont*derx(ll,1,2)
5824         enddo
5825       enddo
5826 cd      do iii=1,nres-3
5827 cd        write (2,*) iii,gcorr_loc(iii)
5828 cd      enddo
5829       endif
5830       eello4=ekont*eel4
5831 cd      write (2,*) 'ekont',ekont
5832 cd      write (iout,*) 'eello4',ekont*eel4
5833       return
5834       end
5835 C---------------------------------------------------------------------------
5836       double precision function eello5(i,j,k,l,jj,kk)
5837       implicit real*8 (a-h,o-z)
5838       include 'DIMENSIONS'
5839       include 'DIMENSIONS.ZSCOPT'
5840       include 'COMMON.IOUNITS'
5841       include 'COMMON.CHAIN'
5842       include 'COMMON.DERIV'
5843       include 'COMMON.INTERACT'
5844       include 'COMMON.CONTACTS'
5845       include 'COMMON.TORSION'
5846       include 'COMMON.VAR'
5847       include 'COMMON.GEO'
5848       double precision pizda(2,2),auxmat(2,2),auxmat1(2,2),vv(2)
5849       double precision ggg1(3),ggg2(3)
5850 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
5851 C                                                                              C
5852 C                            Parallel chains                                   C
5853 C                                                                              C
5854 C          o             o                   o             o                   C
5855 C         /l\           / \             \   / \           / \   /              C
5856 C        /   \         /   \             \ /   \         /   \ /               C
5857 C       j| o |l1       | o |              o| o |         | o |o                C
5858 C     \  |/k\|         |/ \|  /            |/ \|         |/ \|                 C
5859 C      \i/   \         /   \ /             /   \         /   \                 C
5860 C       o    k1             o                                                  C
5861 C         (I)          (II)                (III)          (IV)                 C
5862 C                                                                              C
5863 C      eello5_1        eello5_2            eello5_3       eello5_4             C
5864 C                                                                              C
5865 C                            Antiparallel chains                               C
5866 C                                                                              C
5867 C          o             o                   o             o                   C
5868 C         /j\           / \             \   / \           / \   /              C
5869 C        /   \         /   \             \ /   \         /   \ /               C
5870 C      j1| o |l        | o |              o| o |         | o |o                C
5871 C     \  |/k\|         |/ \|  /            |/ \|         |/ \|                 C
5872 C      \i/   \         /   \ /             /   \         /   \                 C
5873 C       o     k1            o                                                  C
5874 C         (I)          (II)                (III)          (IV)                 C
5875 C                                                                              C
5876 C      eello5_1        eello5_2            eello5_3       eello5_4             C
5877 C                                                                              C
5878 C o denotes a local interaction, vertical lines an electrostatic interaction.  C
5879 C                                                                              C
5880 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
5881 cd      if (i.ne.2 .or. j.ne.6 .or. k.ne.3 .or. l.ne.5) then
5882 cd        eello5=0.0d0
5883 cd        return
5884 cd      endif
5885 cd      write (iout,*)
5886 cd     &   'EELLO5: Contacts have occurred for peptide groups',i,j,
5887 cd     &   ' and',k,l
5888       itk=itortyp(itype(k))
5889       itl=itortyp(itype(l))
5890       itj=itortyp(itype(j))
5891       eello5_1=0.0d0
5892       eello5_2=0.0d0
5893       eello5_3=0.0d0
5894       eello5_4=0.0d0
5895 cd      call checkint5(i,j,k,l,jj,kk,eel5_1_num,eel5_2_num,
5896 cd     &   eel5_3_num,eel5_4_num)
5897       do iii=1,2
5898         do kkk=1,5
5899           do lll=1,3
5900             derx(lll,kkk,iii)=0.0d0
5901           enddo
5902         enddo
5903       enddo
5904 cd      eij=facont_hb(jj,i)
5905 cd      ekl=facont_hb(kk,k)
5906 cd      ekont=eij*ekl
5907 cd      write (iout,*)'Contacts have occurred for peptide groups',
5908 cd     &  i,j,' fcont:',eij,' eij',' and ',k,l
5909 cd      goto 1111
5910 C Contribution from the graph I.
5911 cd      write (2,*) 'AEA  ',AEA(1,1,1),AEA(2,1,1),AEA(1,2,1),AEA(2,2,1)
5912 cd      write (2,*) 'AEAb2',AEAb2(1,1,1),AEAb2(2,1,1)
5913       call transpose2(EUg(1,1,k),auxmat(1,1))
5914       call matmat2(AEA(1,1,1),auxmat(1,1),pizda(1,1))
5915       vv(1)=pizda(1,1)-pizda(2,2)
5916       vv(2)=pizda(1,2)+pizda(2,1)
5917       eello5_1=scalar2(AEAb2(1,1,1),Ub2(1,k))
5918      & +0.5d0*scalar2(vv(1),Dtobr2(1,i))
5919       if (calc_grad) then
5920 C Explicit gradient in virtual-dihedral angles.
5921       if (i.gt.1) g_corr5_loc(i-1)=g_corr5_loc(i-1)
5922      & +ekont*(scalar2(AEAb2derg(1,2,1,1),Ub2(1,k))
5923      & +0.5d0*scalar2(vv(1),Dtobr2der(1,i)))
5924       call transpose2(EUgder(1,1,k),auxmat1(1,1))
5925       call matmat2(AEA(1,1,1),auxmat1(1,1),pizda(1,1))
5926       vv(1)=pizda(1,1)-pizda(2,2)
5927       vv(2)=pizda(1,2)+pizda(2,1)
5928       g_corr5_loc(k-1)=g_corr5_loc(k-1)
5929      & +ekont*(scalar2(AEAb2(1,1,1),Ub2der(1,k))
5930      & +0.5d0*scalar2(vv(1),Dtobr2(1,i)))
5931       call matmat2(AEAderg(1,1,1),auxmat(1,1),pizda(1,1))
5932       vv(1)=pizda(1,1)-pizda(2,2)
5933       vv(2)=pizda(1,2)+pizda(2,1)
5934       if (l.eq.j+1) then
5935         if (l.lt.nres-1) g_corr5_loc(l-1)=g_corr5_loc(l-1)
5936      &   +ekont*(scalar2(AEAb2derg(1,1,1,1),Ub2(1,k))
5937      &   +0.5d0*scalar2(vv(1),Dtobr2(1,i)))
5938       else
5939         if (j.lt.nres-1) g_corr5_loc(j-1)=g_corr5_loc(j-1)
5940      &   +ekont*(scalar2(AEAb2derg(1,1,1,1),Ub2(1,k))
5941      &   +0.5d0*scalar2(vv(1),Dtobr2(1,i)))
5942       endif
5943 C Cartesian gradient
5944       do iii=1,2
5945         do kkk=1,5
5946           do lll=1,3
5947             call matmat2(AEAderx(1,1,lll,kkk,iii,1),auxmat(1,1),
5948      &        pizda(1,1))
5949             vv(1)=pizda(1,1)-pizda(2,2)
5950             vv(2)=pizda(1,2)+pizda(2,1)
5951             derx(lll,kkk,iii)=derx(lll,kkk,iii)
5952      &       +scalar2(AEAb2derx(1,lll,kkk,iii,1,1),Ub2(1,k))
5953      &       +0.5d0*scalar2(vv(1),Dtobr2(1,i))
5954           enddo
5955         enddo
5956       enddo
5957 c      goto 1112
5958       endif
5959 c1111  continue
5960 C Contribution from graph II
5961       call transpose2(EE(1,1,itk),auxmat(1,1))
5962       call matmat2(auxmat(1,1),AEA(1,1,1),pizda(1,1))
5963       vv(1)=pizda(1,1)+pizda(2,2)
5964       vv(2)=pizda(2,1)-pizda(1,2)
5965       eello5_2=scalar2(AEAb1(1,2,1),b1(1,itk))
5966      & -0.5d0*scalar2(vv(1),Ctobr(1,k))
5967       if (calc_grad) then
5968 C Explicit gradient in virtual-dihedral angles.
5969       g_corr5_loc(k-1)=g_corr5_loc(k-1)
5970      & -0.5d0*ekont*scalar2(vv(1),Ctobrder(1,k))
5971       call matmat2(auxmat(1,1),AEAderg(1,1,1),pizda(1,1))
5972       vv(1)=pizda(1,1)+pizda(2,2)
5973       vv(2)=pizda(2,1)-pizda(1,2)
5974       if (l.eq.j+1) then
5975         g_corr5_loc(l-1)=g_corr5_loc(l-1)
5976      &   +ekont*(scalar2(AEAb1derg(1,2,1),b1(1,itk))
5977      &   -0.5d0*scalar2(vv(1),Ctobr(1,k)))
5978       else
5979         g_corr5_loc(j-1)=g_corr5_loc(j-1)
5980      &   +ekont*(scalar2(AEAb1derg(1,2,1),b1(1,itk))
5981      &   -0.5d0*scalar2(vv(1),Ctobr(1,k)))
5982       endif
5983 C Cartesian gradient
5984       do iii=1,2
5985         do kkk=1,5
5986           do lll=1,3
5987             call matmat2(auxmat(1,1),AEAderx(1,1,lll,kkk,iii,1),
5988      &        pizda(1,1))
5989             vv(1)=pizda(1,1)+pizda(2,2)
5990             vv(2)=pizda(2,1)-pizda(1,2)
5991             derx(lll,kkk,iii)=derx(lll,kkk,iii)
5992      &       +scalar2(AEAb1derx(1,lll,kkk,iii,2,1),b1(1,itk))
5993      &       -0.5d0*scalar2(vv(1),Ctobr(1,k))
5994           enddo
5995         enddo
5996       enddo
5997 cd      goto 1112
5998       endif
5999 cd1111  continue
6000       if (l.eq.j+1) then
6001 cd        goto 1110
6002 C Parallel orientation
6003 C Contribution from graph III
6004         call transpose2(EUg(1,1,l),auxmat(1,1))
6005         call matmat2(AEA(1,1,2),auxmat(1,1),pizda(1,1))
6006         vv(1)=pizda(1,1)-pizda(2,2)
6007         vv(2)=pizda(1,2)+pizda(2,1)
6008         eello5_3=scalar2(AEAb2(1,1,2),Ub2(1,l))
6009      &   +0.5d0*scalar2(vv(1),Dtobr2(1,j))
6010         if (calc_grad) then
6011 C Explicit gradient in virtual-dihedral angles.
6012         g_corr5_loc(j-1)=g_corr5_loc(j-1)
6013      &   +ekont*(scalar2(AEAb2derg(1,2,1,2),Ub2(1,l))
6014      &   +0.5d0*scalar2(vv(1),Dtobr2der(1,j)))
6015         call matmat2(AEAderg(1,1,2),auxmat(1,1),pizda(1,1))
6016         vv(1)=pizda(1,1)-pizda(2,2)
6017         vv(2)=pizda(1,2)+pizda(2,1)
6018         g_corr5_loc(k-1)=g_corr5_loc(k-1)
6019      &   +ekont*(scalar2(AEAb2derg(1,1,1,2),Ub2(1,l))
6020      &   +0.5d0*scalar2(vv(1),Dtobr2(1,j)))
6021         call transpose2(EUgder(1,1,l),auxmat1(1,1))
6022         call matmat2(AEA(1,1,2),auxmat1(1,1),pizda(1,1))
6023         vv(1)=pizda(1,1)-pizda(2,2)
6024         vv(2)=pizda(1,2)+pizda(2,1)
6025         g_corr5_loc(l-1)=g_corr5_loc(l-1)
6026      &   +ekont*(scalar2(AEAb2(1,1,2),Ub2der(1,l))
6027      &   +0.5d0*scalar2(vv(1),Dtobr2(1,j)))
6028 C Cartesian gradient
6029         do iii=1,2
6030           do kkk=1,5
6031             do lll=1,3
6032               call matmat2(AEAderx(1,1,lll,kkk,iii,2),auxmat(1,1),
6033      &          pizda(1,1))
6034               vv(1)=pizda(1,1)-pizda(2,2)
6035               vv(2)=pizda(1,2)+pizda(2,1)
6036               derx(lll,kkk,iii)=derx(lll,kkk,iii)
6037      &         +scalar2(AEAb2derx(1,lll,kkk,iii,1,2),Ub2(1,l))
6038      &         +0.5d0*scalar2(vv(1),Dtobr2(1,j))
6039             enddo
6040           enddo
6041         enddo
6042 cd        goto 1112
6043         endif
6044 C Contribution from graph IV
6045 cd1110    continue
6046         call transpose2(EE(1,1,itl),auxmat(1,1))
6047         call matmat2(auxmat(1,1),AEA(1,1,2),pizda(1,1))
6048         vv(1)=pizda(1,1)+pizda(2,2)
6049         vv(2)=pizda(2,1)-pizda(1,2)
6050         eello5_4=scalar2(AEAb1(1,2,2),b1(1,itl))
6051      &   -0.5d0*scalar2(vv(1),Ctobr(1,l))
6052         if (calc_grad) then
6053 C Explicit gradient in virtual-dihedral angles.
6054         g_corr5_loc(l-1)=g_corr5_loc(l-1)
6055      &   -0.5d0*ekont*scalar2(vv(1),Ctobrder(1,l))
6056         call matmat2(auxmat(1,1),AEAderg(1,1,2),pizda(1,1))
6057         vv(1)=pizda(1,1)+pizda(2,2)
6058         vv(2)=pizda(2,1)-pizda(1,2)
6059         g_corr5_loc(k-1)=g_corr5_loc(k-1)
6060      &   +ekont*(scalar2(AEAb1derg(1,2,2),b1(1,itl))
6061      &   -0.5d0*scalar2(vv(1),Ctobr(1,l)))
6062 C Cartesian gradient
6063         do iii=1,2
6064           do kkk=1,5
6065             do lll=1,3
6066               call matmat2(auxmat(1,1),AEAderx(1,1,lll,kkk,iii,2),
6067      &          pizda(1,1))
6068               vv(1)=pizda(1,1)+pizda(2,2)
6069               vv(2)=pizda(2,1)-pizda(1,2)
6070               derx(lll,kkk,iii)=derx(lll,kkk,iii)
6071      &         +scalar2(AEAb1derx(1,lll,kkk,iii,2,2),b1(1,itl))
6072      &         -0.5d0*scalar2(vv(1),Ctobr(1,l))
6073             enddo
6074           enddo
6075         enddo
6076         endif
6077       else
6078 C Antiparallel orientation
6079 C Contribution from graph III
6080 c        goto 1110
6081         call transpose2(EUg(1,1,j),auxmat(1,1))
6082         call matmat2(AEA(1,1,2),auxmat(1,1),pizda(1,1))
6083         vv(1)=pizda(1,1)-pizda(2,2)
6084         vv(2)=pizda(1,2)+pizda(2,1)
6085         eello5_3=scalar2(AEAb2(1,1,2),Ub2(1,j))
6086      &   +0.5d0*scalar2(vv(1),Dtobr2(1,l))
6087         if (calc_grad) then
6088 C Explicit gradient in virtual-dihedral angles.
6089         g_corr5_loc(l-1)=g_corr5_loc(l-1)
6090      &   +ekont*(scalar2(AEAb2derg(1,2,1,2),Ub2(1,j))
6091      &   +0.5d0*scalar2(vv(1),Dtobr2der(1,l)))
6092         call matmat2(AEAderg(1,1,2),auxmat(1,1),pizda(1,1))
6093         vv(1)=pizda(1,1)-pizda(2,2)
6094         vv(2)=pizda(1,2)+pizda(2,1)
6095         g_corr5_loc(k-1)=g_corr5_loc(k-1)
6096      &   +ekont*(scalar2(AEAb2derg(1,1,1,2),Ub2(1,j))
6097      &   +0.5d0*scalar2(vv(1),Dtobr2(1,l)))
6098         call transpose2(EUgder(1,1,j),auxmat1(1,1))
6099         call matmat2(AEA(1,1,2),auxmat1(1,1),pizda(1,1))
6100         vv(1)=pizda(1,1)-pizda(2,2)
6101         vv(2)=pizda(1,2)+pizda(2,1)
6102         g_corr5_loc(j-1)=g_corr5_loc(j-1)
6103      &   +ekont*(scalar2(AEAb2(1,1,2),Ub2der(1,j))
6104      &   +0.5d0*scalar2(vv(1),Dtobr2(1,l)))
6105 C Cartesian gradient
6106         do iii=1,2
6107           do kkk=1,5
6108             do lll=1,3
6109               call matmat2(AEAderx(1,1,lll,kkk,iii,2),auxmat(1,1),
6110      &          pizda(1,1))
6111               vv(1)=pizda(1,1)-pizda(2,2)
6112               vv(2)=pizda(1,2)+pizda(2,1)
6113               derx(lll,kkk,3-iii)=derx(lll,kkk,3-iii)
6114      &         +scalar2(AEAb2derx(1,lll,kkk,iii,1,2),Ub2(1,j))
6115      &         +0.5d0*scalar2(vv(1),Dtobr2(1,l))
6116             enddo
6117           enddo
6118         enddo
6119 cd        goto 1112
6120         endif
6121 C Contribution from graph IV
6122 1110    continue
6123         call transpose2(EE(1,1,itj),auxmat(1,1))
6124         call matmat2(auxmat(1,1),AEA(1,1,2),pizda(1,1))
6125         vv(1)=pizda(1,1)+pizda(2,2)
6126         vv(2)=pizda(2,1)-pizda(1,2)
6127         eello5_4=scalar2(AEAb1(1,2,2),b1(1,itj))
6128      &   -0.5d0*scalar2(vv(1),Ctobr(1,j))
6129         if (calc_grad) then
6130 C Explicit gradient in virtual-dihedral angles.
6131         g_corr5_loc(j-1)=g_corr5_loc(j-1)
6132      &   -0.5d0*ekont*scalar2(vv(1),Ctobrder(1,j))
6133         call matmat2(auxmat(1,1),AEAderg(1,1,2),pizda(1,1))
6134         vv(1)=pizda(1,1)+pizda(2,2)
6135         vv(2)=pizda(2,1)-pizda(1,2)
6136         g_corr5_loc(k-1)=g_corr5_loc(k-1)
6137      &   +ekont*(scalar2(AEAb1derg(1,2,2),b1(1,itj))
6138      &   -0.5d0*scalar2(vv(1),Ctobr(1,j)))
6139 C Cartesian gradient
6140         do iii=1,2
6141           do kkk=1,5
6142             do lll=1,3
6143               call matmat2(auxmat(1,1),AEAderx(1,1,lll,kkk,iii,2),
6144      &          pizda(1,1))
6145               vv(1)=pizda(1,1)+pizda(2,2)
6146               vv(2)=pizda(2,1)-pizda(1,2)
6147               derx(lll,kkk,3-iii)=derx(lll,kkk,3-iii)
6148      &         +scalar2(AEAb1derx(1,lll,kkk,iii,2,2),b1(1,itj))
6149      &         -0.5d0*scalar2(vv(1),Ctobr(1,j))
6150             enddo
6151           enddo
6152         enddo
6153       endif
6154       endif
6155 1112  continue
6156       eel5=eello5_1+eello5_2+eello5_3+eello5_4
6157 cd      if (i.eq.2 .and. j.eq.8 .and. k.eq.3 .and. l.eq.7) then
6158 cd        write (2,*) 'ijkl',i,j,k,l
6159 cd        write (2,*) 'eello5_1',eello5_1,' eello5_2',eello5_2,
6160 cd     &     ' eello5_3',eello5_3,' eello5_4',eello5_4
6161 cd      endif
6162 cd      write(iout,*) 'eello5_1',eello5_1,' eel5_1_num',16*eel5_1_num
6163 cd      write(iout,*) 'eello5_2',eello5_2,' eel5_2_num',16*eel5_2_num
6164 cd      write(iout,*) 'eello5_3',eello5_3,' eel5_3_num',16*eel5_3_num
6165 cd      write(iout,*) 'eello5_4',eello5_4,' eel5_4_num',16*eel5_4_num
6166       if (calc_grad) then
6167       if (j.lt.nres-1) then
6168         j1=j+1
6169         j2=j-1
6170       else
6171         j1=j-1
6172         j2=j-2
6173       endif
6174       if (l.lt.nres-1) then
6175         l1=l+1
6176         l2=l-1
6177       else
6178         l1=l-1
6179         l2=l-2
6180       endif
6181 cd      eij=1.0d0
6182 cd      ekl=1.0d0
6183 cd      ekont=1.0d0
6184 cd      write (2,*) 'eij',eij,' ekl',ekl,' ekont',ekont
6185       do ll=1,3
6186         ggg1(ll)=eel5*g_contij(ll,1)
6187         ggg2(ll)=eel5*g_contij(ll,2)
6188 cold        ghalf=0.5d0*eel5*ekl*gacont_hbr(ll,jj,i)
6189         ghalf=0.5d0*ggg1(ll)
6190 cd        ghalf=0.0d0
6191         gradcorr5(ll,i)=gradcorr5(ll,i)+ghalf+ekont*derx(ll,2,1)
6192         gradcorr5(ll,i+1)=gradcorr5(ll,i+1)+ekont*derx(ll,3,1)
6193         gradcorr5(ll,j)=gradcorr5(ll,j)+ghalf+ekont*derx(ll,4,1)
6194         gradcorr5(ll,j1)=gradcorr5(ll,j1)+ekont*derx(ll,5,1)
6195 cold        ghalf=0.5d0*eel5*eij*gacont_hbr(ll,kk,k)
6196         ghalf=0.5d0*ggg2(ll)
6197 cd        ghalf=0.0d0
6198         gradcorr5(ll,k)=gradcorr5(ll,k)+ghalf+ekont*derx(ll,2,2)
6199         gradcorr5(ll,k+1)=gradcorr5(ll,k+1)+ekont*derx(ll,3,2)
6200         gradcorr5(ll,l)=gradcorr5(ll,l)+ghalf+ekont*derx(ll,4,2)
6201         gradcorr5(ll,l1)=gradcorr5(ll,l1)+ekont*derx(ll,5,2)
6202       enddo
6203 cd      goto 1112
6204       do m=i+1,j-1
6205         do ll=1,3
6206 cold          gradcorr5(ll,m)=gradcorr5(ll,m)+eel5*ekl*gacont_hbr(ll,jj,i)
6207           gradcorr5(ll,m)=gradcorr5(ll,m)+ggg1(ll)
6208         enddo
6209       enddo
6210       do m=k+1,l-1
6211         do ll=1,3
6212 cold          gradcorr5(ll,m)=gradcorr5(ll,m)+eel5*eij*gacont_hbr(ll,kk,k)
6213           gradcorr5(ll,m)=gradcorr5(ll,m)+ggg2(ll)
6214         enddo
6215       enddo
6216 c1112  continue
6217       do m=i+2,j2
6218         do ll=1,3
6219           gradcorr5(ll,m)=gradcorr5(ll,m)+ekont*derx(ll,1,1)
6220         enddo
6221       enddo
6222       do m=k+2,l2
6223         do ll=1,3
6224           gradcorr5(ll,m)=gradcorr5(ll,m)+ekont*derx(ll,1,2)
6225         enddo
6226       enddo
6227 cd      do iii=1,nres-3
6228 cd        write (2,*) iii,g_corr5_loc(iii)
6229 cd      enddo
6230       endif
6231       eello5=ekont*eel5
6232 cd      write (2,*) 'ekont',ekont
6233 cd      write (iout,*) 'eello5',ekont*eel5
6234       return
6235       end
6236 c--------------------------------------------------------------------------
6237       double precision function eello6(i,j,k,l,jj,kk)
6238       implicit real*8 (a-h,o-z)
6239       include 'DIMENSIONS'
6240       include 'DIMENSIONS.ZSCOPT'
6241       include 'COMMON.IOUNITS'
6242       include 'COMMON.CHAIN'
6243       include 'COMMON.DERIV'
6244       include 'COMMON.INTERACT'
6245       include 'COMMON.CONTACTS'
6246       include 'COMMON.TORSION'
6247       include 'COMMON.VAR'
6248       include 'COMMON.GEO'
6249       include 'COMMON.FFIELD'
6250       double precision ggg1(3),ggg2(3)
6251 cd      if (i.ne.1 .or. j.ne.3 .or. k.ne.2 .or. l.ne.4) then
6252 cd        eello6=0.0d0
6253 cd        return
6254 cd      endif
6255 cd      write (iout,*)
6256 cd     &   'EELLO6: Contacts have occurred for peptide groups',i,j,
6257 cd     &   ' and',k,l
6258       eello6_1=0.0d0
6259       eello6_2=0.0d0
6260       eello6_3=0.0d0
6261       eello6_4=0.0d0
6262       eello6_5=0.0d0
6263       eello6_6=0.0d0
6264 cd      call checkint6(i,j,k,l,jj,kk,eel6_1_num,eel6_2_num,
6265 cd     &   eel6_3_num,eel6_4_num,eel6_5_num,eel6_6_num)
6266       do iii=1,2
6267         do kkk=1,5
6268           do lll=1,3
6269             derx(lll,kkk,iii)=0.0d0
6270           enddo
6271         enddo
6272       enddo
6273 cd      eij=facont_hb(jj,i)
6274 cd      ekl=facont_hb(kk,k)
6275 cd      ekont=eij*ekl
6276 cd      eij=1.0d0
6277 cd      ekl=1.0d0
6278 cd      ekont=1.0d0
6279       if (l.eq.j+1) then
6280         eello6_1=eello6_graph1(i,j,k,l,1,.false.)
6281         eello6_2=eello6_graph1(j,i,l,k,2,.false.)
6282         eello6_3=eello6_graph2(i,j,k,l,jj,kk,.false.)
6283         eello6_4=eello6_graph4(i,j,k,l,jj,kk,1,.false.)
6284         eello6_5=eello6_graph4(j,i,l,k,jj,kk,2,.false.)
6285         eello6_6=eello6_graph3(i,j,k,l,jj,kk,.false.)
6286       else
6287         eello6_1=eello6_graph1(i,j,k,l,1,.false.)
6288         eello6_2=eello6_graph1(l,k,j,i,2,.true.)
6289         eello6_3=eello6_graph2(i,l,k,j,jj,kk,.true.)
6290         eello6_4=eello6_graph4(i,j,k,l,jj,kk,1,.false.)
6291         if (wturn6.eq.0.0d0 .or. j.ne.i+4) then
6292           eello6_5=eello6_graph4(l,k,j,i,kk,jj,2,.true.)
6293         else
6294           eello6_5=0.0d0
6295         endif
6296         eello6_6=eello6_graph3(i,l,k,j,jj,kk,.true.)
6297       endif
6298 C If turn contributions are considered, they will be handled separately.
6299       eel6=eello6_1+eello6_2+eello6_3+eello6_4+eello6_5+eello6_6
6300 cd      write(iout,*) 'eello6_1',eello6_1,' eel6_1_num',16*eel6_1_num
6301 cd      write(iout,*) 'eello6_2',eello6_2,' eel6_2_num',16*eel6_2_num
6302 cd      write(iout,*) 'eello6_3',eello6_3,' eel6_3_num',16*eel6_3_num
6303 cd      write(iout,*) 'eello6_4',eello6_4,' eel6_4_num',16*eel6_4_num
6304 cd      write(iout,*) 'eello6_5',eello6_5,' eel6_5_num',16*eel6_5_num
6305 cd      write(iout,*) 'eello6_6',eello6_6,' eel6_6_num',16*eel6_6_num
6306 cd      goto 1112
6307       if (calc_grad) then
6308       if (j.lt.nres-1) then
6309         j1=j+1
6310         j2=j-1
6311       else
6312         j1=j-1
6313         j2=j-2
6314       endif
6315       if (l.lt.nres-1) then
6316         l1=l+1
6317         l2=l-1
6318       else
6319         l1=l-1
6320         l2=l-2
6321       endif
6322       do ll=1,3
6323         ggg1(ll)=eel6*g_contij(ll,1)
6324         ggg2(ll)=eel6*g_contij(ll,2)
6325 cold        ghalf=0.5d0*eel6*ekl*gacont_hbr(ll,jj,i)
6326         ghalf=0.5d0*ggg1(ll)
6327 cd        ghalf=0.0d0
6328         gradcorr6(ll,i)=gradcorr6(ll,i)+ghalf+ekont*derx(ll,2,1)
6329         gradcorr6(ll,i+1)=gradcorr6(ll,i+1)+ekont*derx(ll,3,1)
6330         gradcorr6(ll,j)=gradcorr6(ll,j)+ghalf+ekont*derx(ll,4,1)
6331         gradcorr6(ll,j1)=gradcorr6(ll,j1)+ekont*derx(ll,5,1)
6332         ghalf=0.5d0*ggg2(ll)
6333 cold        ghalf=0.5d0*eel6*eij*gacont_hbr(ll,kk,k)
6334 cd        ghalf=0.0d0
6335         gradcorr6(ll,k)=gradcorr6(ll,k)+ghalf+ekont*derx(ll,2,2)
6336         gradcorr6(ll,k+1)=gradcorr6(ll,k+1)+ekont*derx(ll,3,2)
6337         gradcorr6(ll,l)=gradcorr6(ll,l)+ghalf+ekont*derx(ll,4,2)
6338         gradcorr6(ll,l1)=gradcorr6(ll,l1)+ekont*derx(ll,5,2)
6339       enddo
6340 cd      goto 1112
6341       do m=i+1,j-1
6342         do ll=1,3
6343 cold          gradcorr6(ll,m)=gradcorr6(ll,m)+eel6*ekl*gacont_hbr(ll,jj,i)
6344           gradcorr6(ll,m)=gradcorr6(ll,m)+ggg1(ll)
6345         enddo
6346       enddo
6347       do m=k+1,l-1
6348         do ll=1,3
6349 cold          gradcorr6(ll,m)=gradcorr6(ll,m)+eel6*eij*gacont_hbr(ll,kk,k)
6350           gradcorr6(ll,m)=gradcorr6(ll,m)+ggg2(ll)
6351         enddo
6352       enddo
6353 1112  continue
6354       do m=i+2,j2
6355         do ll=1,3
6356           gradcorr6(ll,m)=gradcorr6(ll,m)+ekont*derx(ll,1,1)
6357         enddo
6358       enddo
6359       do m=k+2,l2
6360         do ll=1,3
6361           gradcorr6(ll,m)=gradcorr6(ll,m)+ekont*derx(ll,1,2)
6362         enddo
6363       enddo
6364 cd      do iii=1,nres-3
6365 cd        write (2,*) iii,g_corr6_loc(iii)
6366 cd      enddo
6367       endif
6368       eello6=ekont*eel6
6369 cd      write (2,*) 'ekont',ekont
6370 cd      write (iout,*) 'eello6',ekont*eel6
6371       return
6372       end
6373 c--------------------------------------------------------------------------
6374       double precision function eello6_graph1(i,j,k,l,imat,swap)
6375       implicit real*8 (a-h,o-z)
6376       include 'DIMENSIONS'
6377       include 'DIMENSIONS.ZSCOPT'
6378       include 'COMMON.IOUNITS'
6379       include 'COMMON.CHAIN'
6380       include 'COMMON.DERIV'
6381       include 'COMMON.INTERACT'
6382       include 'COMMON.CONTACTS'
6383       include 'COMMON.TORSION'
6384       include 'COMMON.VAR'
6385       include 'COMMON.GEO'
6386       double precision vv(2),vv1(2),pizda(2,2),auxmat(2,2),pizda1(2,2)
6387       logical swap
6388       logical lprn
6389       common /kutas/ lprn
6390 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
6391 C                                                                              C
6392 C      Parallel       Antiparallel                                             C
6393 C                                                                              C
6394 C          o             o                                                     C
6395 C         /l\           /j\                                                    C
6396 C        /   \         /   \                                                   C
6397 C       /| o |         | o |\                                                  C
6398 C     \ j|/k\|  /   \  |/k\|l /                                                C
6399 C      \ /   \ /     \ /   \ /                                                 C
6400 C       o     o       o     o                                                  C
6401 C       i             i                                                        C
6402 C                                                                              C
6403 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
6404       itk=itortyp(itype(k))
6405       s1= scalar2(AEAb1(1,2,imat),CUgb2(1,i))
6406       s2=-scalar2(AEAb2(1,1,imat),Ug2Db1t(1,k))
6407       s3= scalar2(AEAb2(1,1,imat),CUgb2(1,k))
6408       call transpose2(EUgC(1,1,k),auxmat(1,1))
6409       call matmat2(AEA(1,1,imat),auxmat(1,1),pizda1(1,1))
6410       vv1(1)=pizda1(1,1)-pizda1(2,2)
6411       vv1(2)=pizda1(1,2)+pizda1(2,1)
6412       s4=0.5d0*scalar2(vv1(1),Dtobr2(1,i))
6413       vv(1)=AEAb1(1,2,imat)*b1(1,itk)-AEAb1(2,2,imat)*b1(2,itk)
6414       vv(2)=AEAb1(1,2,imat)*b1(2,itk)+AEAb1(2,2,imat)*b1(1,itk)
6415       s5=scalar2(vv(1),Dtobr2(1,i))
6416 cd      write (2,*) 's1',s1,' s2',s2,' s3',s3,' s4', s4,' s5',s5
6417       eello6_graph1=-0.5d0*(s1+s2+s3+s4+s5)
6418       if (.not. calc_grad) return
6419       if (i.gt.1) g_corr6_loc(i-1)=g_corr6_loc(i-1)
6420      & -0.5d0*ekont*(scalar2(AEAb1(1,2,imat),CUgb2der(1,i))
6421      & -scalar2(AEAb2derg(1,2,1,imat),Ug2Db1t(1,k))
6422      & +scalar2(AEAb2derg(1,2,1,imat),CUgb2(1,k))
6423      & +0.5d0*scalar2(vv1(1),Dtobr2der(1,i))
6424      & +scalar2(vv(1),Dtobr2der(1,i)))
6425       call matmat2(AEAderg(1,1,imat),auxmat(1,1),pizda1(1,1))
6426       vv1(1)=pizda1(1,1)-pizda1(2,2)
6427       vv1(2)=pizda1(1,2)+pizda1(2,1)
6428       vv(1)=AEAb1derg(1,2,imat)*b1(1,itk)-AEAb1derg(2,2,imat)*b1(2,itk)
6429       vv(2)=AEAb1derg(1,2,imat)*b1(2,itk)+AEAb1derg(2,2,imat)*b1(1,itk)
6430       if (l.eq.j+1) then
6431         g_corr6_loc(l-1)=g_corr6_loc(l-1)
6432      & +ekont*(-0.5d0*(scalar2(AEAb1derg(1,2,imat),CUgb2(1,i))
6433      & -scalar2(AEAb2derg(1,1,1,imat),Ug2Db1t(1,k))
6434      & +scalar2(AEAb2derg(1,1,1,imat),CUgb2(1,k))
6435      & +0.5d0*scalar2(vv1(1),Dtobr2(1,i))+scalar2(vv(1),Dtobr2(1,i))))
6436       else
6437         g_corr6_loc(j-1)=g_corr6_loc(j-1)
6438      & +ekont*(-0.5d0*(scalar2(AEAb1derg(1,2,imat),CUgb2(1,i))
6439      & -scalar2(AEAb2derg(1,1,1,imat),Ug2Db1t(1,k))
6440      & +scalar2(AEAb2derg(1,1,1,imat),CUgb2(1,k))
6441      & +0.5d0*scalar2(vv1(1),Dtobr2(1,i))+scalar2(vv(1),Dtobr2(1,i))))
6442       endif
6443       call transpose2(EUgCder(1,1,k),auxmat(1,1))
6444       call matmat2(AEA(1,1,imat),auxmat(1,1),pizda1(1,1))
6445       vv1(1)=pizda1(1,1)-pizda1(2,2)
6446       vv1(2)=pizda1(1,2)+pizda1(2,1)
6447       if (k.gt.1) g_corr6_loc(k-1)=g_corr6_loc(k-1)
6448      & +ekont*(-0.5d0*(-scalar2(AEAb2(1,1,imat),Ug2Db1tder(1,k))
6449      & +scalar2(AEAb2(1,1,imat),CUgb2der(1,k))
6450      & +0.5d0*scalar2(vv1(1),Dtobr2(1,i))))
6451       do iii=1,2
6452         if (swap) then
6453           ind=3-iii
6454         else
6455           ind=iii
6456         endif
6457         do kkk=1,5
6458           do lll=1,3
6459             s1= scalar2(AEAb1derx(1,lll,kkk,iii,2,imat),CUgb2(1,i))
6460             s2=-scalar2(AEAb2derx(1,lll,kkk,iii,1,imat),Ug2Db1t(1,k))
6461             s3= scalar2(AEAb2derx(1,lll,kkk,iii,1,imat),CUgb2(1,k))
6462             call transpose2(EUgC(1,1,k),auxmat(1,1))
6463             call matmat2(AEAderx(1,1,lll,kkk,iii,imat),auxmat(1,1),
6464      &        pizda1(1,1))
6465             vv1(1)=pizda1(1,1)-pizda1(2,2)
6466             vv1(2)=pizda1(1,2)+pizda1(2,1)
6467             s4=0.5d0*scalar2(vv1(1),Dtobr2(1,i))
6468             vv(1)=AEAb1derx(1,lll,kkk,iii,2,imat)*b1(1,itk)
6469      &       -AEAb1derx(2,lll,kkk,iii,2,imat)*b1(2,itk)
6470             vv(2)=AEAb1derx(1,lll,kkk,iii,2,imat)*b1(2,itk)
6471      &       +AEAb1derx(2,lll,kkk,iii,2,imat)*b1(1,itk)
6472             s5=scalar2(vv(1),Dtobr2(1,i))
6473             derx(lll,kkk,ind)=derx(lll,kkk,ind)-0.5d0*(s1+s2+s3+s4+s5)
6474           enddo
6475         enddo
6476       enddo
6477       return
6478       end
6479 c----------------------------------------------------------------------------
6480       double precision function eello6_graph2(i,j,k,l,jj,kk,swap)
6481       implicit real*8 (a-h,o-z)
6482       include 'DIMENSIONS'
6483       include 'DIMENSIONS.ZSCOPT'
6484       include 'COMMON.IOUNITS'
6485       include 'COMMON.CHAIN'
6486       include 'COMMON.DERIV'
6487       include 'COMMON.INTERACT'
6488       include 'COMMON.CONTACTS'
6489       include 'COMMON.TORSION'
6490       include 'COMMON.VAR'
6491       include 'COMMON.GEO'
6492       logical swap
6493       double precision vv(2),pizda(2,2),auxmat(2,2),auxvec(2),
6494      & auxvec1(2),auxvec2(2),auxmat1(2,2)
6495       logical lprn
6496       common /kutas/ lprn
6497 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
6498 C                                                                              C
6499 C      Parallel       Antiparallel                                             C
6500 C                                                                              C
6501 C          o             o                                                     C
6502 C     \   /l\           /j\   /                                                C
6503 C      \ /   \         /   \ /                                                 C
6504 C       o| o |         | o |o                                                  C
6505 C     \ j|/k\|      \  |/k\|l                                                  C
6506 C      \ /   \       \ /   \                                                   C
6507 C       o             o                                                        C
6508 C       i             i                                                        C
6509 C                                                                              C
6510 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
6511 cd      write (2,*) 'eello6_graph2: i,',i,' j',j,' k',k,' l',l
6512 C AL 7/4/01 s1 would occur in the sixth-order moment,
6513 C           but not in a cluster cumulant
6514 #ifdef MOMENT
6515       s1=dip(1,jj,i)*dip(1,kk,k)
6516 #endif
6517       call matvec2(ADtEA1(1,1,1),Ub2(1,k),auxvec(1))
6518       s2=-0.5d0*scalar2(Ub2(1,i),auxvec(1))
6519       call matvec2(ADtEA(1,1,2),Ub2(1,l),auxvec1(1))
6520       s3=-0.5d0*scalar2(Ub2(1,j),auxvec1(1))
6521       call transpose2(EUg(1,1,k),auxmat(1,1))
6522       call matmat2(ADtEA1(1,1,1),auxmat(1,1),pizda(1,1))
6523       vv(1)=pizda(1,1)-pizda(2,2)
6524       vv(2)=pizda(1,2)+pizda(2,1)
6525       s4=-0.25d0*scalar2(vv(1),Dtobr2(1,i))
6526 cd      write (2,*) 'eello6_graph2:','s1',s1,' s2',s2,' s3',s3,' s4',s4
6527 #ifdef MOMENT
6528       eello6_graph2=-(s1+s2+s3+s4)
6529 #else
6530       eello6_graph2=-(s2+s3+s4)
6531 #endif
6532 c      eello6_graph2=-s3
6533       if (.not. calc_grad) return
6534 C Derivatives in gamma(i-1)
6535       if (i.gt.1) then
6536 #ifdef MOMENT
6537         s1=dipderg(1,jj,i)*dip(1,kk,k)
6538 #endif
6539         s2=-0.5d0*scalar2(Ub2der(1,i),auxvec(1))
6540         call matvec2(ADtEAderg(1,1,1,2),Ub2(1,l),auxvec2(1))
6541         s3=-0.5d0*scalar2(Ub2(1,j),auxvec2(1))
6542         s4=-0.25d0*scalar2(vv(1),Dtobr2der(1,i))
6543 #ifdef MOMENT
6544         g_corr6_loc(i-1)=g_corr6_loc(i-1)-ekont*(s1+s2+s3+s4)
6545 #else
6546         g_corr6_loc(i-1)=g_corr6_loc(i-1)-ekont*(s2+s3+s4)
6547 #endif
6548 c        g_corr6_loc(i-1)=g_corr6_loc(i-1)-s3
6549       endif
6550 C Derivatives in gamma(k-1)
6551 #ifdef MOMENT
6552       s1=dip(1,jj,i)*dipderg(1,kk,k)
6553 #endif
6554       call matvec2(ADtEA1(1,1,1),Ub2der(1,k),auxvec2(1))
6555       s2=-0.5d0*scalar2(Ub2(1,i),auxvec2(1))
6556       call matvec2(ADtEAderg(1,1,2,2),Ub2(1,l),auxvec2(1))
6557       s3=-0.5d0*scalar2(Ub2(1,j),auxvec2(1))
6558       call transpose2(EUgder(1,1,k),auxmat1(1,1))
6559       call matmat2(ADtEA1(1,1,1),auxmat1(1,1),pizda(1,1))
6560       vv(1)=pizda(1,1)-pizda(2,2)
6561       vv(2)=pizda(1,2)+pizda(2,1)
6562       s4=-0.25d0*scalar2(vv(1),Dtobr2(1,i))
6563 #ifdef MOMENT
6564       g_corr6_loc(k-1)=g_corr6_loc(k-1)-ekont*(s1+s2+s3+s4)
6565 #else
6566       g_corr6_loc(k-1)=g_corr6_loc(k-1)-ekont*(s2+s3+s4)
6567 #endif
6568 c      g_corr6_loc(k-1)=g_corr6_loc(k-1)-s3
6569 C Derivatives in gamma(j-1) or gamma(l-1)
6570       if (j.gt.1) then
6571 #ifdef MOMENT
6572         s1=dipderg(3,jj,i)*dip(1,kk,k)
6573 #endif
6574         call matvec2(ADtEA1derg(1,1,1,1),Ub2(1,k),auxvec2(1))
6575         s2=-0.5d0*scalar2(Ub2(1,i),auxvec2(1))
6576         s3=-0.5d0*scalar2(Ub2der(1,j),auxvec1(1))
6577         call matmat2(ADtEA1derg(1,1,1,1),auxmat(1,1),pizda(1,1))
6578         vv(1)=pizda(1,1)-pizda(2,2)
6579         vv(2)=pizda(1,2)+pizda(2,1)
6580         s4=-0.25d0*scalar2(vv(1),Dtobr2(1,i))
6581 #ifdef MOMENT
6582         if (swap) then
6583           g_corr6_loc(l-1)=g_corr6_loc(l-1)-ekont*s1
6584         else
6585           g_corr6_loc(j-1)=g_corr6_loc(j-1)-ekont*s1
6586         endif
6587 #endif
6588         g_corr6_loc(j-1)=g_corr6_loc(j-1)-ekont*(s2+s3+s4)
6589 c        g_corr6_loc(j-1)=g_corr6_loc(j-1)-s3
6590       endif
6591 C Derivatives in gamma(l-1) or gamma(j-1)
6592       if (l.gt.1) then
6593 #ifdef MOMENT
6594         s1=dip(1,jj,i)*dipderg(3,kk,k)
6595 #endif
6596         call matvec2(ADtEA1derg(1,1,2,1),Ub2(1,k),auxvec2(1))
6597         s2=-0.5d0*scalar2(Ub2(1,i),auxvec2(1))
6598         call matvec2(ADtEA(1,1,2),Ub2der(1,l),auxvec2(1))
6599         s3=-0.5d0*scalar2(Ub2(1,j),auxvec2(1))
6600         call matmat2(ADtEA1derg(1,1,2,1),auxmat(1,1),pizda(1,1))
6601         vv(1)=pizda(1,1)-pizda(2,2)
6602         vv(2)=pizda(1,2)+pizda(2,1)
6603         s4=-0.25d0*scalar2(vv(1),Dtobr2(1,i))
6604 #ifdef MOMENT
6605         if (swap) then
6606           g_corr6_loc(j-1)=g_corr6_loc(j-1)-ekont*s1
6607         else
6608           g_corr6_loc(l-1)=g_corr6_loc(l-1)-ekont*s1
6609         endif
6610 #endif
6611         g_corr6_loc(l-1)=g_corr6_loc(l-1)-ekont*(s2+s3+s4)
6612 c        g_corr6_loc(l-1)=g_corr6_loc(l-1)-s3
6613       endif
6614 C Cartesian derivatives.
6615       if (lprn) then
6616         write (2,*) 'In eello6_graph2'
6617         do iii=1,2
6618           write (2,*) 'iii=',iii
6619           do kkk=1,5
6620             write (2,*) 'kkk=',kkk
6621             do jjj=1,2
6622               write (2,'(3(2f10.5),5x)')
6623      &        ((ADtEA1derx(jjj,mmm,lll,kkk,iii,1),mmm=1,2),lll=1,3)
6624             enddo
6625           enddo
6626         enddo
6627       endif
6628       do iii=1,2
6629         do kkk=1,5
6630           do lll=1,3
6631 #ifdef MOMENT
6632             if (iii.eq.1) then
6633               s1=dipderx(lll,kkk,1,jj,i)*dip(1,kk,k)
6634             else
6635               s1=dip(1,jj,i)*dipderx(lll,kkk,1,kk,k)
6636             endif
6637 #endif
6638             call matvec2(ADtEA1derx(1,1,lll,kkk,iii,1),Ub2(1,k),
6639      &        auxvec(1))
6640             s2=-0.5d0*scalar2(Ub2(1,i),auxvec(1))
6641             call matvec2(ADtEAderx(1,1,lll,kkk,iii,2),Ub2(1,l),
6642      &        auxvec(1))
6643             s3=-0.5d0*scalar2(Ub2(1,j),auxvec(1))
6644             call transpose2(EUg(1,1,k),auxmat(1,1))
6645             call matmat2(ADtEA1derx(1,1,lll,kkk,iii,1),auxmat(1,1),
6646      &        pizda(1,1))
6647             vv(1)=pizda(1,1)-pizda(2,2)
6648             vv(2)=pizda(1,2)+pizda(2,1)
6649             s4=-0.25d0*scalar2(vv(1),Dtobr2(1,i))
6650 cd            write (2,*) 's1',s1,' s2',s2,' s3',s3,' s4',s4
6651 #ifdef MOMENT
6652             derx(lll,kkk,iii)=derx(lll,kkk,iii)-(s1+s2+s4)
6653 #else
6654             derx(lll,kkk,iii)=derx(lll,kkk,iii)-(s2+s4)
6655 #endif
6656             if (swap) then
6657               derx(lll,kkk,3-iii)=derx(lll,kkk,3-iii)-s3
6658             else
6659               derx(lll,kkk,iii)=derx(lll,kkk,iii)-s3
6660             endif
6661           enddo
6662         enddo
6663       enddo
6664       return
6665       end
6666 c----------------------------------------------------------------------------
6667       double precision function eello6_graph3(i,j,k,l,jj,kk,swap)
6668       implicit real*8 (a-h,o-z)
6669       include 'DIMENSIONS'
6670       include 'DIMENSIONS.ZSCOPT'
6671       include 'COMMON.IOUNITS'
6672       include 'COMMON.CHAIN'
6673       include 'COMMON.DERIV'
6674       include 'COMMON.INTERACT'
6675       include 'COMMON.CONTACTS'
6676       include 'COMMON.TORSION'
6677       include 'COMMON.VAR'
6678       include 'COMMON.GEO'
6679       double precision vv(2),pizda(2,2),auxmat(2,2),auxvec(2)
6680       logical swap
6681 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
6682 C                                                                              C
6683 C      Parallel       Antiparallel                                             C
6684 C                                                                              C
6685 C          o             o                                                     C
6686 C         /l\   /   \   /j\                                                    C
6687 C        /   \ /     \ /   \                                                   C
6688 C       /| o |o       o| o |\                                                  C
6689 C       j|/k\|  /      |/k\|l /                                                C
6690 C        /   \ /       /   \ /                                                 C
6691 C       /     o       /     o                                                  C
6692 C       i             i                                                        C
6693 C                                                                              C
6694 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
6695 C
6696 C 4/7/01 AL Component s1 was removed, because it pertains to the respective
6697 C           energy moment and not to the cluster cumulant.
6698       iti=itortyp(itype(i))
6699       if (j.lt.nres-1) then
6700         itj1=itortyp(itype(j+1))
6701       else
6702         itj1=ntortyp+1
6703       endif
6704       itk=itortyp(itype(k))
6705       itk1=itortyp(itype(k+1))
6706       if (l.lt.nres-1) then
6707         itl1=itortyp(itype(l+1))
6708       else
6709         itl1=ntortyp+1
6710       endif
6711 #ifdef MOMENT
6712       s1=dip(4,jj,i)*dip(4,kk,k)
6713 #endif
6714       call matvec2(AECA(1,1,1),b1(1,itk1),auxvec(1))
6715       s2=0.5d0*scalar2(b1(1,itk),auxvec(1))
6716       call matvec2(AECA(1,1,2),b1(1,itl1),auxvec(1))
6717       s3=0.5d0*scalar2(b1(1,itj1),auxvec(1))
6718       call transpose2(EE(1,1,itk),auxmat(1,1))
6719       call matmat2(auxmat(1,1),AECA(1,1,1),pizda(1,1))
6720       vv(1)=pizda(1,1)+pizda(2,2)
6721       vv(2)=pizda(2,1)-pizda(1,2)
6722       s4=-0.25d0*scalar2(vv(1),Ctobr(1,k))
6723 cd      write (2,*) 'eello6_graph3:','s1',s1,' s2',s2,' s3',s3,' s4',s4
6724 #ifdef MOMENT
6725       eello6_graph3=-(s1+s2+s3+s4)
6726 #else
6727       eello6_graph3=-(s2+s3+s4)
6728 #endif
6729 c      eello6_graph3=-s4
6730       if (.not. calc_grad) return
6731 C Derivatives in gamma(k-1)
6732       call matvec2(AECAderg(1,1,2),b1(1,itl1),auxvec(1))
6733       s3=0.5d0*scalar2(b1(1,itj1),auxvec(1))
6734       s4=-0.25d0*scalar2(vv(1),Ctobrder(1,k))
6735       g_corr6_loc(k-1)=g_corr6_loc(k-1)-ekont*(s3+s4)
6736 C Derivatives in gamma(l-1)
6737       call matvec2(AECAderg(1,1,1),b1(1,itk1),auxvec(1))
6738       s2=0.5d0*scalar2(b1(1,itk),auxvec(1))
6739       call matmat2(auxmat(1,1),AECAderg(1,1,1),pizda(1,1))
6740       vv(1)=pizda(1,1)+pizda(2,2)
6741       vv(2)=pizda(2,1)-pizda(1,2)
6742       s4=-0.25d0*scalar2(vv(1),Ctobr(1,k))
6743       g_corr6_loc(l-1)=g_corr6_loc(l-1)-ekont*(s2+s4)
6744 C Cartesian derivatives.
6745       do iii=1,2
6746         do kkk=1,5
6747           do lll=1,3
6748 #ifdef MOMENT
6749             if (iii.eq.1) then
6750               s1=dipderx(lll,kkk,4,jj,i)*dip(4,kk,k)
6751             else
6752               s1=dip(4,jj,i)*dipderx(lll,kkk,4,kk,k)
6753             endif
6754 #endif
6755             call matvec2(AECAderx(1,1,lll,kkk,iii,1),b1(1,itk1),
6756      &        auxvec(1))
6757             s2=0.5d0*scalar2(b1(1,itk),auxvec(1))
6758             call matvec2(AECAderx(1,1,lll,kkk,iii,2),b1(1,itl1),
6759      &        auxvec(1))
6760             s3=0.5d0*scalar2(b1(1,itj1),auxvec(1))
6761             call matmat2(auxmat(1,1),AECAderx(1,1,lll,kkk,iii,1),
6762      &        pizda(1,1))
6763             vv(1)=pizda(1,1)+pizda(2,2)
6764             vv(2)=pizda(2,1)-pizda(1,2)
6765             s4=-0.25d0*scalar2(vv(1),Ctobr(1,k))
6766 #ifdef MOMENT
6767             derx(lll,kkk,iii)=derx(lll,kkk,iii)-(s1+s2+s4)
6768 #else
6769             derx(lll,kkk,iii)=derx(lll,kkk,iii)-(s2+s4)
6770 #endif
6771             if (swap) then
6772               derx(lll,kkk,3-iii)=derx(lll,kkk,3-iii)-s3
6773             else
6774               derx(lll,kkk,iii)=derx(lll,kkk,iii)-s3
6775             endif
6776 c            derx(lll,kkk,iii)=derx(lll,kkk,iii)-s4
6777           enddo
6778         enddo
6779       enddo
6780       return
6781       end
6782 c----------------------------------------------------------------------------
6783       double precision function eello6_graph4(i,j,k,l,jj,kk,imat,swap)
6784       implicit real*8 (a-h,o-z)
6785       include 'DIMENSIONS'
6786       include 'DIMENSIONS.ZSCOPT'
6787       include 'COMMON.IOUNITS'
6788       include 'COMMON.CHAIN'
6789       include 'COMMON.DERIV'
6790       include 'COMMON.INTERACT'
6791       include 'COMMON.CONTACTS'
6792       include 'COMMON.TORSION'
6793       include 'COMMON.VAR'
6794       include 'COMMON.GEO'
6795       include 'COMMON.FFIELD'
6796       double precision vv(2),pizda(2,2),auxmat(2,2),auxvec(2),
6797      & auxvec1(2),auxmat1(2,2)
6798       logical swap
6799 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
6800 C                                                                              C
6801 C      Parallel       Antiparallel                                             C
6802 C                                                                              C
6803 C          o             o                                                     C
6804 C         /l\   /   \   /j\                                                    C
6805 C        /   \ /     \ /   \                                                   C
6806 C       /| o |o       o| o |\                                                  C
6807 C     \ j|/k\|      \  |/k\|l                                                  C
6808 C      \ /   \       \ /   \                                                   C
6809 C       o     \       o     \                                                  C
6810 C       i             i                                                        C
6811 C                                                                              C
6812 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
6813 C
6814 C 4/7/01 AL Component s1 was removed, because it pertains to the respective
6815 C           energy moment and not to the cluster cumulant.
6816 cd      write (2,*) 'eello_graph4: wturn6',wturn6
6817       iti=itortyp(itype(i))
6818       itj=itortyp(itype(j))
6819       if (j.lt.nres-1) then
6820         itj1=itortyp(itype(j+1))
6821       else
6822         itj1=ntortyp+1
6823       endif
6824       itk=itortyp(itype(k))
6825       if (k.lt.nres-1) then
6826         itk1=itortyp(itype(k+1))
6827       else
6828         itk1=ntortyp+1
6829       endif
6830       itl=itortyp(itype(l))
6831       if (l.lt.nres-1) then
6832         itl1=itortyp(itype(l+1))
6833       else
6834         itl1=ntortyp+1
6835       endif
6836 cd      write (2,*) 'eello6_graph4:','i',i,' j',j,' k',k,' l',l
6837 cd      write (2,*) 'iti',iti,' itj',itj,' itj1',itj1,' itk',itk,
6838 cd     & ' itl',itl,' itl1',itl1
6839 #ifdef MOMENT
6840       if (imat.eq.1) then
6841         s1=dip(3,jj,i)*dip(3,kk,k)
6842       else
6843         s1=dip(2,jj,j)*dip(2,kk,l)
6844       endif
6845 #endif
6846       call matvec2(AECA(1,1,imat),Ub2(1,k),auxvec(1))
6847       s2=0.5d0*scalar2(Ub2(1,i),auxvec(1))
6848       if (j.eq.l+1) then
6849         call matvec2(ADtEA1(1,1,3-imat),b1(1,itj1),auxvec1(1))
6850         s3=-0.5d0*scalar2(b1(1,itj),auxvec1(1))
6851       else
6852         call matvec2(ADtEA1(1,1,3-imat),b1(1,itl1),auxvec1(1))
6853         s3=-0.5d0*scalar2(b1(1,itl),auxvec1(1))
6854       endif
6855       call transpose2(EUg(1,1,k),auxmat(1,1))
6856       call matmat2(AECA(1,1,imat),auxmat(1,1),pizda(1,1))
6857       vv(1)=pizda(1,1)-pizda(2,2)
6858       vv(2)=pizda(2,1)+pizda(1,2)
6859       s4=0.25d0*scalar2(vv(1),Dtobr2(1,i))
6860 cd      write (2,*) 'eello6_graph4:','s1',s1,' s2',s2,' s3',s3,' s4',s4
6861 #ifdef MOMENT
6862       eello6_graph4=-(s1+s2+s3+s4)
6863 #else
6864       eello6_graph4=-(s2+s3+s4)
6865 #endif
6866       if (.not. calc_grad) return
6867 C Derivatives in gamma(i-1)
6868       if (i.gt.1) then
6869 #ifdef MOMENT
6870         if (imat.eq.1) then
6871           s1=dipderg(2,jj,i)*dip(3,kk,k)
6872         else
6873           s1=dipderg(4,jj,j)*dip(2,kk,l)
6874         endif
6875 #endif
6876         s2=0.5d0*scalar2(Ub2der(1,i),auxvec(1))
6877         if (j.eq.l+1) then
6878           call matvec2(ADtEA1derg(1,1,1,3-imat),b1(1,itj1),auxvec1(1))
6879           s3=-0.5d0*scalar2(b1(1,itj),auxvec1(1))
6880         else
6881           call matvec2(ADtEA1derg(1,1,1,3-imat),b1(1,itl1),auxvec1(1))
6882           s3=-0.5d0*scalar2(b1(1,itl),auxvec1(1))
6883         endif
6884         s4=0.25d0*scalar2(vv(1),Dtobr2der(1,i))
6885         if (wturn6.gt.0.0d0 .and. k.eq.l+4 .and. i.eq.j+2) then
6886 cd          write (2,*) 'turn6 derivatives'
6887 #ifdef MOMENT
6888           gel_loc_turn6(i-1)=gel_loc_turn6(i-1)-ekont*(s1+s2+s3+s4)
6889 #else
6890           gel_loc_turn6(i-1)=gel_loc_turn6(i-1)-ekont*(s2+s3+s4)
6891 #endif
6892         else
6893 #ifdef MOMENT
6894           g_corr6_loc(i-1)=g_corr6_loc(i-1)-ekont*(s1+s2+s3+s4)
6895 #else
6896           g_corr6_loc(i-1)=g_corr6_loc(i-1)-ekont*(s2+s3+s4)
6897 #endif
6898         endif
6899       endif
6900 C Derivatives in gamma(k-1)
6901 #ifdef MOMENT
6902       if (imat.eq.1) then
6903         s1=dip(3,jj,i)*dipderg(2,kk,k)
6904       else
6905         s1=dip(2,jj,j)*dipderg(4,kk,l)
6906       endif
6907 #endif
6908       call matvec2(AECA(1,1,imat),Ub2der(1,k),auxvec1(1))
6909       s2=0.5d0*scalar2(Ub2(1,i),auxvec1(1))
6910       if (j.eq.l+1) then
6911         call matvec2(ADtEA1derg(1,1,2,3-imat),b1(1,itj1),auxvec1(1))
6912         s3=-0.5d0*scalar2(b1(1,itj),auxvec1(1))
6913       else
6914         call matvec2(ADtEA1derg(1,1,2,3-imat),b1(1,itl1),auxvec1(1))
6915         s3=-0.5d0*scalar2(b1(1,itl),auxvec1(1))
6916       endif
6917       call transpose2(EUgder(1,1,k),auxmat1(1,1))
6918       call matmat2(AECA(1,1,imat),auxmat1(1,1),pizda(1,1))
6919       vv(1)=pizda(1,1)-pizda(2,2)
6920       vv(2)=pizda(2,1)+pizda(1,2)
6921       s4=0.25d0*scalar2(vv(1),Dtobr2(1,i))
6922       if (wturn6.gt.0.0d0 .and. k.eq.l+4 .and. i.eq.j+2) then
6923 #ifdef MOMENT
6924         gel_loc_turn6(k-1)=gel_loc_turn6(k-1)-ekont*(s1+s2+s3+s4)
6925 #else
6926         gel_loc_turn6(k-1)=gel_loc_turn6(k-1)-ekont*(s2+s3+s4)
6927 #endif
6928       else
6929 #ifdef MOMENT
6930         g_corr6_loc(k-1)=g_corr6_loc(k-1)-ekont*(s1+s2+s3+s4)
6931 #else
6932         g_corr6_loc(k-1)=g_corr6_loc(k-1)-ekont*(s2+s3+s4)
6933 #endif
6934       endif
6935 C Derivatives in gamma(j-1) or gamma(l-1)
6936       if (l.eq.j+1 .and. l.gt.1) then
6937         call matvec2(AECAderg(1,1,imat),Ub2(1,k),auxvec(1))
6938         s2=0.5d0*scalar2(Ub2(1,i),auxvec(1))
6939         call matmat2(AECAderg(1,1,imat),auxmat(1,1),pizda(1,1))
6940         vv(1)=pizda(1,1)-pizda(2,2)
6941         vv(2)=pizda(2,1)+pizda(1,2)
6942         s4=0.25d0*scalar2(vv(1),Dtobr2(1,i))
6943         g_corr6_loc(l-1)=g_corr6_loc(l-1)-ekont*(s2+s4)
6944       else if (j.gt.1) then
6945         call matvec2(AECAderg(1,1,imat),Ub2(1,k),auxvec(1))
6946         s2=0.5d0*scalar2(Ub2(1,i),auxvec(1))
6947         call matmat2(AECAderg(1,1,imat),auxmat(1,1),pizda(1,1))
6948         vv(1)=pizda(1,1)-pizda(2,2)
6949         vv(2)=pizda(2,1)+pizda(1,2)
6950         s4=0.25d0*scalar2(vv(1),Dtobr2(1,i))
6951         if (wturn6.gt.0.0d0 .and. k.eq.l+4 .and. i.eq.j+2) then
6952           gel_loc_turn6(j-1)=gel_loc_turn6(j-1)-ekont*(s2+s4)
6953         else
6954           g_corr6_loc(j-1)=g_corr6_loc(j-1)-ekont*(s2+s4)
6955         endif
6956       endif
6957 C Cartesian derivatives.
6958       do iii=1,2
6959         do kkk=1,5
6960           do lll=1,3
6961 #ifdef MOMENT
6962             if (iii.eq.1) then
6963               if (imat.eq.1) then
6964                 s1=dipderx(lll,kkk,3,jj,i)*dip(3,kk,k)
6965               else
6966                 s1=dipderx(lll,kkk,2,jj,j)*dip(2,kk,l)
6967               endif
6968             else
6969               if (imat.eq.1) then
6970                 s1=dip(3,jj,i)*dipderx(lll,kkk,3,kk,k)
6971               else
6972                 s1=dip(2,jj,j)*dipderx(lll,kkk,2,kk,l)
6973               endif
6974             endif
6975 #endif
6976             call matvec2(AECAderx(1,1,lll,kkk,iii,imat),Ub2(1,k),
6977      &        auxvec(1))
6978             s2=0.5d0*scalar2(Ub2(1,i),auxvec(1))
6979             if (j.eq.l+1) then
6980               call matvec2(ADtEA1derx(1,1,lll,kkk,iii,3-imat),
6981      &          b1(1,itj1),auxvec(1))
6982               s3=-0.5d0*scalar2(b1(1,itj),auxvec(1))
6983             else
6984               call matvec2(ADtEA1derx(1,1,lll,kkk,iii,3-imat),
6985      &          b1(1,itl1),auxvec(1))
6986               s3=-0.5d0*scalar2(b1(1,itl),auxvec(1))
6987             endif
6988             call matmat2(AECAderx(1,1,lll,kkk,iii,imat),auxmat(1,1),
6989      &        pizda(1,1))
6990             vv(1)=pizda(1,1)-pizda(2,2)
6991             vv(2)=pizda(2,1)+pizda(1,2)
6992             s4=0.25d0*scalar2(vv(1),Dtobr2(1,i))
6993             if (swap) then
6994               if (wturn6.gt.0.0d0 .and. k.eq.l+4 .and. i.eq.j+2) then
6995 #ifdef MOMENT
6996                 derx_turn(lll,kkk,3-iii)=derx_turn(lll,kkk,3-iii)
6997      &             -(s1+s2+s4)
6998 #else
6999                 derx_turn(lll,kkk,3-iii)=derx_turn(lll,kkk,3-iii)
7000      &             -(s2+s4)
7001 #endif
7002                 derx_turn(lll,kkk,iii)=derx_turn(lll,kkk,iii)-s3
7003               else
7004 #ifdef MOMENT
7005                 derx(lll,kkk,3-iii)=derx(lll,kkk,3-iii)-(s1+s2+s4)
7006 #else
7007                 derx(lll,kkk,3-iii)=derx(lll,kkk,3-iii)-(s2+s4)
7008 #endif
7009                 derx(lll,kkk,iii)=derx(lll,kkk,iii)-s3
7010               endif
7011             else
7012 #ifdef MOMENT
7013               derx(lll,kkk,iii)=derx(lll,kkk,iii)-(s1+s2+s4)
7014 #else
7015               derx(lll,kkk,iii)=derx(lll,kkk,iii)-(s2+s4)
7016 #endif
7017               if (l.eq.j+1) then
7018                 derx(lll,kkk,iii)=derx(lll,kkk,iii)-s3
7019               else
7020                 derx(lll,kkk,3-iii)=derx(lll,kkk,3-iii)-s3
7021               endif
7022             endif
7023           enddo
7024         enddo
7025       enddo
7026       return
7027       end
7028 c----------------------------------------------------------------------------
7029       double precision function eello_turn6(i,jj,kk)
7030       implicit real*8 (a-h,o-z)
7031       include 'DIMENSIONS'
7032       include 'DIMENSIONS.ZSCOPT'
7033       include 'COMMON.IOUNITS'
7034       include 'COMMON.CHAIN'
7035       include 'COMMON.DERIV'
7036       include 'COMMON.INTERACT'
7037       include 'COMMON.CONTACTS'
7038       include 'COMMON.TORSION'
7039       include 'COMMON.VAR'
7040       include 'COMMON.GEO'
7041       double precision vtemp1(2),vtemp2(2),vtemp3(2),vtemp4(2),
7042      &  atemp(2,2),auxmat(2,2),achuj_temp(2,2),gtemp(2,2),gvec(2),
7043      &  ggg1(3),ggg2(3)
7044       double precision vtemp1d(2),vtemp2d(2),vtemp3d(2),vtemp4d(2),
7045      &  atempd(2,2),auxmatd(2,2),achuj_tempd(2,2),gtempd(2,2),gvecd(2)
7046 C 4/7/01 AL Components s1, s8, and s13 were removed, because they pertain to
7047 C           the respective energy moment and not to the cluster cumulant.
7048       eello_turn6=0.0d0
7049       j=i+4
7050       k=i+1
7051       l=i+3
7052       iti=itortyp(itype(i))
7053       itk=itortyp(itype(k))
7054       itk1=itortyp(itype(k+1))
7055       itl=itortyp(itype(l))
7056       itj=itortyp(itype(j))
7057 cd      write (2,*) 'itk',itk,' itk1',itk1,' itl',itl,' itj',itj
7058 cd      write (2,*) 'i',i,' k',k,' j',j,' l',l
7059 cd      if (i.ne.1 .or. j.ne.3 .or. k.ne.2 .or. l.ne.4) then
7060 cd        eello6=0.0d0
7061 cd        return
7062 cd      endif
7063 cd      write (iout,*)
7064 cd     &   'EELLO6: Contacts have occurred for peptide groups',i,j,
7065 cd     &   ' and',k,l
7066 cd      call checkint_turn6(i,jj,kk,eel_turn6_num)
7067       do iii=1,2
7068         do kkk=1,5
7069           do lll=1,3
7070             derx_turn(lll,kkk,iii)=0.0d0
7071           enddo
7072         enddo
7073       enddo
7074 cd      eij=1.0d0
7075 cd      ekl=1.0d0
7076 cd      ekont=1.0d0
7077       eello6_5=eello6_graph4(l,k,j,i,kk,jj,2,.true.)
7078 cd      eello6_5=0.0d0
7079 cd      write (2,*) 'eello6_5',eello6_5
7080 #ifdef MOMENT
7081       call transpose2(AEA(1,1,1),auxmat(1,1))
7082       call matmat2(EUg(1,1,i+1),auxmat(1,1),auxmat(1,1))
7083       ss1=scalar2(Ub2(1,i+2),b1(1,itl))
7084       s1 = (auxmat(1,1)+auxmat(2,2))*ss1
7085 #else
7086       s1 = 0.0d0
7087 #endif
7088       call matvec2(EUg(1,1,i+2),b1(1,itl),vtemp1(1))
7089       call matvec2(AEA(1,1,1),vtemp1(1),vtemp1(1))
7090       s2 = scalar2(b1(1,itk),vtemp1(1))
7091 #ifdef MOMENT
7092       call transpose2(AEA(1,1,2),atemp(1,1))
7093       call matmat2(atemp(1,1),EUg(1,1,i+4),atemp(1,1))
7094       call matvec2(Ug2(1,1,i+2),dd(1,1,itk1),vtemp2(1))
7095       s8 = -(atemp(1,1)+atemp(2,2))*scalar2(cc(1,1,itl),vtemp2(1))
7096 #else
7097       s8=0.0d0
7098 #endif
7099       call matmat2(EUg(1,1,i+3),AEA(1,1,2),auxmat(1,1))
7100       call matvec2(auxmat(1,1),Ub2(1,i+4),vtemp3(1))
7101       s12 = scalar2(Ub2(1,i+2),vtemp3(1))
7102 #ifdef MOMENT
7103       call transpose2(a_chuj(1,1,kk,i+1),achuj_temp(1,1))
7104       call matmat2(achuj_temp(1,1),EUg(1,1,i+2),gtemp(1,1))
7105       call matmat2(gtemp(1,1),EUg(1,1,i+3),gtemp(1,1))
7106       call matvec2(a_chuj(1,1,jj,i),Ub2(1,i+4),vtemp4(1))
7107       ss13 = scalar2(b1(1,itk),vtemp4(1))
7108       s13 = (gtemp(1,1)+gtemp(2,2))*ss13
7109 #else
7110       s13=0.0d0
7111 #endif
7112 c      write (2,*) 's1,s2,s8,s12,s13',s1,s2,s8,s12,s13
7113 c      s1=0.0d0
7114 c      s2=0.0d0
7115 c      s8=0.0d0
7116 c      s12=0.0d0
7117 c      s13=0.0d0
7118       eel_turn6 = eello6_5 - 0.5d0*(s1+s2+s12+s8+s13)
7119       if (calc_grad) then
7120 C Derivatives in gamma(i+2)
7121 #ifdef MOMENT
7122       call transpose2(AEA(1,1,1),auxmatd(1,1))
7123       call matmat2(EUgder(1,1,i+1),auxmatd(1,1),auxmatd(1,1))
7124       s1d = (auxmatd(1,1)+auxmatd(2,2))*ss1
7125       call transpose2(AEAderg(1,1,2),atempd(1,1))
7126       call matmat2(atempd(1,1),EUg(1,1,i+4),atempd(1,1))
7127       s8d = -(atempd(1,1)+atempd(2,2))*scalar2(cc(1,1,itl),vtemp2(1))
7128 #else
7129       s8d=0.0d0
7130 #endif
7131       call matmat2(EUg(1,1,i+3),AEAderg(1,1,2),auxmatd(1,1))
7132       call matvec2(auxmatd(1,1),Ub2(1,i+4),vtemp3d(1))
7133       s12d = scalar2(Ub2(1,i+2),vtemp3d(1))
7134 c      s1d=0.0d0
7135 c      s2d=0.0d0
7136 c      s8d=0.0d0
7137 c      s12d=0.0d0
7138 c      s13d=0.0d0
7139       gel_loc_turn6(i)=gel_loc_turn6(i)-0.5d0*ekont*(s1d+s8d+s12d)
7140 C Derivatives in gamma(i+3)
7141 #ifdef MOMENT
7142       call transpose2(AEA(1,1,1),auxmatd(1,1))
7143       call matmat2(EUg(1,1,i+1),auxmatd(1,1),auxmatd(1,1))
7144       ss1d=scalar2(Ub2der(1,i+2),b1(1,itl))
7145       s1d = (auxmatd(1,1)+auxmatd(2,2))*ss1d
7146 #else
7147       s1d=0.0d0
7148 #endif
7149       call matvec2(EUgder(1,1,i+2),b1(1,itl),vtemp1d(1))
7150       call matvec2(AEA(1,1,1),vtemp1d(1),vtemp1d(1))
7151       s2d = scalar2(b1(1,itk),vtemp1d(1))
7152 #ifdef MOMENT
7153       call matvec2(Ug2der(1,1,i+2),dd(1,1,itk1),vtemp2d(1))
7154       s8d = -(atemp(1,1)+atemp(2,2))*scalar2(cc(1,1,itl),vtemp2d(1))
7155 #endif
7156       s12d = scalar2(Ub2der(1,i+2),vtemp3(1))
7157 #ifdef MOMENT
7158       call matmat2(achuj_temp(1,1),EUgder(1,1,i+2),gtempd(1,1))
7159       call matmat2(gtempd(1,1),EUg(1,1,i+3),gtempd(1,1))
7160       s13d = (gtempd(1,1)+gtempd(2,2))*ss13
7161 #else
7162       s13d=0.0d0
7163 #endif
7164 c      s1d=0.0d0
7165 c      s2d=0.0d0
7166 c      s8d=0.0d0
7167 c      s12d=0.0d0
7168 c      s13d=0.0d0
7169 #ifdef MOMENT
7170       gel_loc_turn6(i+1)=gel_loc_turn6(i+1)
7171      &               -0.5d0*ekont*(s1d+s2d+s8d+s12d+s13d)
7172 #else
7173       gel_loc_turn6(i+1)=gel_loc_turn6(i+1)
7174      &               -0.5d0*ekont*(s2d+s12d)
7175 #endif
7176 C Derivatives in gamma(i+4)
7177       call matmat2(EUgder(1,1,i+3),AEA(1,1,2),auxmatd(1,1))
7178       call matvec2(auxmatd(1,1),Ub2(1,i+4),vtemp3d(1))
7179       s12d = scalar2(Ub2(1,i+2),vtemp3d(1))
7180 #ifdef MOMENT
7181       call matmat2(achuj_temp(1,1),EUg(1,1,i+2),gtempd(1,1))
7182       call matmat2(gtempd(1,1),EUgder(1,1,i+3),gtempd(1,1))
7183       s13d = (gtempd(1,1)+gtempd(2,2))*ss13
7184 #else
7185       s13d = 0.0d0
7186 #endif
7187 c      s1d=0.0d0
7188 c      s2d=0.0d0
7189 c      s8d=0.0d0
7190 C      s12d=0.0d0
7191 c      s13d=0.0d0
7192 #ifdef MOMENT
7193       gel_loc_turn6(i+2)=gel_loc_turn6(i+2)-0.5d0*ekont*(s12d+s13d)
7194 #else
7195       gel_loc_turn6(i+2)=gel_loc_turn6(i+2)-0.5d0*ekont*(s12d)
7196 #endif
7197 C Derivatives in gamma(i+5)
7198 #ifdef MOMENT
7199       call transpose2(AEAderg(1,1,1),auxmatd(1,1))
7200       call matmat2(EUg(1,1,i+1),auxmatd(1,1),auxmatd(1,1))
7201       s1d = (auxmatd(1,1)+auxmatd(2,2))*ss1
7202 #else
7203       s1d = 0.0d0
7204 #endif
7205       call matvec2(EUg(1,1,i+2),b1(1,itl),vtemp1d(1))
7206       call matvec2(AEAderg(1,1,1),vtemp1d(1),vtemp1d(1))
7207       s2d = scalar2(b1(1,itk),vtemp1d(1))
7208 #ifdef MOMENT
7209       call transpose2(AEA(1,1,2),atempd(1,1))
7210       call matmat2(atempd(1,1),EUgder(1,1,i+4),atempd(1,1))
7211       s8d = -(atempd(1,1)+atempd(2,2))*scalar2(cc(1,1,itl),vtemp2(1))
7212 #else
7213       s8d = 0.0d0
7214 #endif
7215       call matvec2(auxmat(1,1),Ub2der(1,i+4),vtemp3d(1))
7216       s12d = scalar2(Ub2(1,i+2),vtemp3d(1))
7217 #ifdef MOMENT
7218       call matvec2(a_chuj(1,1,jj,i),Ub2der(1,i+4),vtemp4d(1))
7219       ss13d = scalar2(b1(1,itk),vtemp4d(1))
7220       s13d = (gtemp(1,1)+gtemp(2,2))*ss13d
7221 #else
7222       s13d = 0.0d0
7223 #endif
7224 c      s1d=0.0d0
7225 c      s2d=0.0d0
7226 c      s8d=0.0d0
7227 c      s12d=0.0d0
7228 c      s13d=0.0d0
7229 #ifdef MOMENT
7230       gel_loc_turn6(i+3)=gel_loc_turn6(i+3)
7231      &               -0.5d0*ekont*(s1d+s2d+s8d+s12d+s13d)
7232 #else
7233       gel_loc_turn6(i+3)=gel_loc_turn6(i+3)
7234      &               -0.5d0*ekont*(s2d+s12d)
7235 #endif
7236 C Cartesian derivatives
7237       do iii=1,2
7238         do kkk=1,5
7239           do lll=1,3
7240 #ifdef MOMENT
7241             call transpose2(AEAderx(1,1,lll,kkk,iii,1),auxmatd(1,1))
7242             call matmat2(EUg(1,1,i+1),auxmatd(1,1),auxmatd(1,1))
7243             s1d = (auxmatd(1,1)+auxmatd(2,2))*ss1
7244 #else
7245             s1d = 0.0d0
7246 #endif
7247             call matvec2(EUg(1,1,i+2),b1(1,itl),vtemp1(1))
7248             call matvec2(AEAderx(1,1,lll,kkk,iii,1),vtemp1(1),
7249      &          vtemp1d(1))
7250             s2d = scalar2(b1(1,itk),vtemp1d(1))
7251 #ifdef MOMENT
7252             call transpose2(AEAderx(1,1,lll,kkk,iii,2),atempd(1,1))
7253             call matmat2(atempd(1,1),EUg(1,1,i+4),atempd(1,1))
7254             s8d = -(atempd(1,1)+atempd(2,2))*
7255      &           scalar2(cc(1,1,itl),vtemp2(1))
7256 #else
7257             s8d = 0.0d0
7258 #endif
7259             call matmat2(EUg(1,1,i+3),AEAderx(1,1,lll,kkk,iii,2),
7260      &           auxmatd(1,1))
7261             call matvec2(auxmatd(1,1),Ub2(1,i+4),vtemp3d(1))
7262             s12d = scalar2(Ub2(1,i+2),vtemp3d(1))
7263 c      s1d=0.0d0
7264 c      s2d=0.0d0
7265 c      s8d=0.0d0
7266 c      s12d=0.0d0
7267 c      s13d=0.0d0
7268 #ifdef MOMENT
7269             derx_turn(lll,kkk,iii) = derx_turn(lll,kkk,iii)
7270      &        - 0.5d0*(s1d+s2d)
7271 #else
7272             derx_turn(lll,kkk,iii) = derx_turn(lll,kkk,iii)
7273      &        - 0.5d0*s2d
7274 #endif
7275 #ifdef MOMENT
7276             derx_turn(lll,kkk,3-iii) = derx_turn(lll,kkk,3-iii)
7277      &        - 0.5d0*(s8d+s12d)
7278 #else
7279             derx_turn(lll,kkk,3-iii) = derx_turn(lll,kkk,3-iii)
7280      &        - 0.5d0*s12d
7281 #endif
7282           enddo
7283         enddo
7284       enddo
7285 #ifdef MOMENT
7286       do kkk=1,5
7287         do lll=1,3
7288           call transpose2(a_chuj_der(1,1,lll,kkk,kk,i+1),
7289      &      achuj_tempd(1,1))
7290           call matmat2(achuj_tempd(1,1),EUg(1,1,i+2),gtempd(1,1))
7291           call matmat2(gtempd(1,1),EUg(1,1,i+3),gtempd(1,1))
7292           s13d=(gtempd(1,1)+gtempd(2,2))*ss13
7293           derx_turn(lll,kkk,2) = derx_turn(lll,kkk,2)-0.5d0*s13d
7294           call matvec2(a_chuj_der(1,1,lll,kkk,jj,i),Ub2(1,i+4),
7295      &      vtemp4d(1))
7296           ss13d = scalar2(b1(1,itk),vtemp4d(1))
7297           s13d = (gtemp(1,1)+gtemp(2,2))*ss13d
7298           derx_turn(lll,kkk,1) = derx_turn(lll,kkk,1)-0.5d0*s13d
7299         enddo
7300       enddo
7301 #endif
7302 cd      write(iout,*) 'eel6_turn6',eel_turn6,' eel_turn6_num',
7303 cd     &  16*eel_turn6_num
7304 cd      goto 1112
7305       if (j.lt.nres-1) then
7306         j1=j+1
7307         j2=j-1
7308       else
7309         j1=j-1
7310         j2=j-2
7311       endif
7312       if (l.lt.nres-1) then
7313         l1=l+1
7314         l2=l-1
7315       else
7316         l1=l-1
7317         l2=l-2
7318       endif
7319       do ll=1,3
7320         ggg1(ll)=eel_turn6*g_contij(ll,1)
7321         ggg2(ll)=eel_turn6*g_contij(ll,2)
7322         ghalf=0.5d0*ggg1(ll)
7323 cd        ghalf=0.0d0
7324         gcorr6_turn(ll,i)=gcorr6_turn(ll,i)+ghalf
7325      &    +ekont*derx_turn(ll,2,1)
7326         gcorr6_turn(ll,i+1)=gcorr6_turn(ll,i+1)+ekont*derx_turn(ll,3,1)
7327         gcorr6_turn(ll,j)=gcorr6_turn(ll,j)+ghalf
7328      &    +ekont*derx_turn(ll,4,1)
7329         gcorr6_turn(ll,j1)=gcorr6_turn(ll,j1)+ekont*derx_turn(ll,5,1)
7330         ghalf=0.5d0*ggg2(ll)
7331 cd        ghalf=0.0d0
7332         gcorr6_turn(ll,k)=gcorr6_turn(ll,k)+ghalf
7333      &    +ekont*derx_turn(ll,2,2)
7334         gcorr6_turn(ll,k+1)=gcorr6_turn(ll,k+1)+ekont*derx_turn(ll,3,2)
7335         gcorr6_turn(ll,l)=gcorr6_turn(ll,l)+ghalf
7336      &    +ekont*derx_turn(ll,4,2)
7337         gcorr6_turn(ll,l1)=gcorr6_turn(ll,l1)+ekont*derx_turn(ll,5,2)
7338       enddo
7339 cd      goto 1112
7340       do m=i+1,j-1
7341         do ll=1,3
7342           gcorr6_turn(ll,m)=gcorr6_turn(ll,m)+ggg1(ll)
7343         enddo
7344       enddo
7345       do m=k+1,l-1
7346         do ll=1,3
7347           gcorr6_turn(ll,m)=gcorr6_turn(ll,m)+ggg2(ll)
7348         enddo
7349       enddo
7350 1112  continue
7351       do m=i+2,j2
7352         do ll=1,3
7353           gcorr6_turn(ll,m)=gcorr6_turn(ll,m)+ekont*derx_turn(ll,1,1)
7354         enddo
7355       enddo
7356       do m=k+2,l2
7357         do ll=1,3
7358           gcorr6_turn(ll,m)=gcorr6_turn(ll,m)+ekont*derx_turn(ll,1,2)
7359         enddo
7360       enddo
7361 cd      do iii=1,nres-3
7362 cd        write (2,*) iii,g_corr6_loc(iii)
7363 cd      enddo
7364       endif
7365       eello_turn6=ekont*eel_turn6
7366 cd      write (2,*) 'ekont',ekont
7367 cd      write (2,*) 'eel_turn6',ekont*eel_turn6
7368       return
7369       end
7370 crc-------------------------------------------------
7371       SUBROUTINE MATVEC2(A1,V1,V2)
7372       implicit real*8 (a-h,o-z)
7373       include 'DIMENSIONS'
7374       DIMENSION A1(2,2),V1(2),V2(2)
7375 c      DO 1 I=1,2
7376 c        VI=0.0
7377 c        DO 3 K=1,2
7378 c    3     VI=VI+A1(I,K)*V1(K)
7379 c        Vaux(I)=VI
7380 c    1 CONTINUE
7381
7382       vaux1=a1(1,1)*v1(1)+a1(1,2)*v1(2)
7383       vaux2=a1(2,1)*v1(1)+a1(2,2)*v1(2)
7384
7385       v2(1)=vaux1
7386       v2(2)=vaux2
7387       END
7388 C---------------------------------------
7389       SUBROUTINE MATMAT2(A1,A2,A3)
7390       implicit real*8 (a-h,o-z)
7391       include 'DIMENSIONS'
7392       DIMENSION A1(2,2),A2(2,2),A3(2,2)
7393 c      DIMENSION AI3(2,2)
7394 c        DO  J=1,2
7395 c          A3IJ=0.0
7396 c          DO K=1,2
7397 c           A3IJ=A3IJ+A1(I,K)*A2(K,J)
7398 c          enddo
7399 c          A3(I,J)=A3IJ
7400 c       enddo
7401 c      enddo
7402
7403       ai3_11=a1(1,1)*a2(1,1)+a1(1,2)*a2(2,1)
7404       ai3_12=a1(1,1)*a2(1,2)+a1(1,2)*a2(2,2)
7405       ai3_21=a1(2,1)*a2(1,1)+a1(2,2)*a2(2,1)
7406       ai3_22=a1(2,1)*a2(1,2)+a1(2,2)*a2(2,2)
7407
7408       A3(1,1)=AI3_11
7409       A3(2,1)=AI3_21
7410       A3(1,2)=AI3_12
7411       A3(2,2)=AI3_22
7412       END
7413
7414 c-------------------------------------------------------------------------
7415       double precision function scalar2(u,v)
7416       implicit none
7417       double precision u(2),v(2)
7418       double precision sc
7419       integer i
7420       scalar2=u(1)*v(1)+u(2)*v(2)
7421       return
7422       end
7423
7424 C-----------------------------------------------------------------------------
7425
7426       subroutine transpose2(a,at)
7427       implicit none
7428       double precision a(2,2),at(2,2)
7429       at(1,1)=a(1,1)
7430       at(1,2)=a(2,1)
7431       at(2,1)=a(1,2)
7432       at(2,2)=a(2,2)
7433       return
7434       end
7435 c--------------------------------------------------------------------------
7436       subroutine transpose(n,a,at)
7437       implicit none
7438       integer n,i,j
7439       double precision a(n,n),at(n,n)
7440       do i=1,n
7441         do j=1,n
7442           at(j,i)=a(i,j)
7443         enddo
7444       enddo
7445       return
7446       end
7447 C---------------------------------------------------------------------------
7448       subroutine prodmat3(a1,a2,kk,transp,prod)
7449       implicit none
7450       integer i,j
7451       double precision a1(2,2),a2(2,2),a2t(2,2),kk(2,2),prod(2,2)
7452       logical transp
7453 crc      double precision auxmat(2,2),prod_(2,2)
7454
7455       if (transp) then
7456 crc        call transpose2(kk(1,1),auxmat(1,1))
7457 crc        call matmat2(a1(1,1),auxmat(1,1),auxmat(1,1))
7458 crc        call matmat2(auxmat(1,1),a2(1,1),prod_(1,1))
7459
7460            prod(1,1)=(a1(1,1)*kk(1,1)+a1(1,2)*kk(1,2))*a2(1,1)
7461      & +(a1(1,1)*kk(2,1)+a1(1,2)*kk(2,2))*a2(2,1)
7462            prod(1,2)=(a1(1,1)*kk(1,1)+a1(1,2)*kk(1,2))*a2(1,2)
7463      & +(a1(1,1)*kk(2,1)+a1(1,2)*kk(2,2))*a2(2,2)
7464            prod(2,1)=(a1(2,1)*kk(1,1)+a1(2,2)*kk(1,2))*a2(1,1)
7465      & +(a1(2,1)*kk(2,1)+a1(2,2)*kk(2,2))*a2(2,1)
7466            prod(2,2)=(a1(2,1)*kk(1,1)+a1(2,2)*kk(1,2))*a2(1,2)
7467      & +(a1(2,1)*kk(2,1)+a1(2,2)*kk(2,2))*a2(2,2)
7468
7469       else
7470 crc        call matmat2(a1(1,1),kk(1,1),auxmat(1,1))
7471 crc        call matmat2(auxmat(1,1),a2(1,1),prod_(1,1))
7472
7473            prod(1,1)=(a1(1,1)*kk(1,1)+a1(1,2)*kk(2,1))*a2(1,1)
7474      &  +(a1(1,1)*kk(1,2)+a1(1,2)*kk(2,2))*a2(2,1)
7475            prod(1,2)=(a1(1,1)*kk(1,1)+a1(1,2)*kk(2,1))*a2(1,2)
7476      &  +(a1(1,1)*kk(1,2)+a1(1,2)*kk(2,2))*a2(2,2)
7477            prod(2,1)=(a1(2,1)*kk(1,1)+a1(2,2)*kk(2,1))*a2(1,1)
7478      &  +(a1(2,1)*kk(1,2)+a1(2,2)*kk(2,2))*a2(2,1)
7479            prod(2,2)=(a1(2,1)*kk(1,1)+a1(2,2)*kk(2,1))*a2(1,2)
7480      &  +(a1(2,1)*kk(1,2)+a1(2,2)*kk(2,2))*a2(2,2)
7481
7482       endif
7483 c      call transpose2(a2(1,1),a2t(1,1))
7484
7485 crc      print *,transp
7486 crc      print *,((prod_(i,j),i=1,2),j=1,2)
7487 crc      print *,((prod(i,j),i=1,2),j=1,2)
7488
7489       return
7490       end
7491 C-----------------------------------------------------------------------------
7492       double precision function scalar(u,v)
7493       implicit none
7494       double precision u(3),v(3)
7495       double precision sc
7496       integer i
7497       sc=0.0d0
7498       do i=1,3
7499         sc=sc+u(i)*v(i)
7500       enddo
7501       scalar=sc
7502       return
7503       end
7504