wham & cluster src_MD-M new HOMOL energy
[unres.git] / source / wham / src-M / energy_p_new.F
index fcc52c0..0ac883c 100644 (file)
@@ -2,6 +2,7 @@
       implicit real*8 (a-h,o-z)
       include 'DIMENSIONS'
       include 'DIMENSIONS.ZSCOPT'
+      include 'DIMENSIONS.FREE'
 
 #ifndef ISNAN
       external proc_proc
@@ -22,6 +23,7 @@ cMS$ATTRIBUTES C ::  proc_proc
       include 'COMMON.INTERACT'
       include 'COMMON.SBRIDGE'
       include 'COMMON.CHAIN'
+      include 'COMMON.CONTROL'
       double precision fact(6)
 cd      write(iout, '(a,i2)')'Calling etotal ipot=',ipot
 cd    print *,'nnt=',nnt,' nct=',nct
@@ -98,29 +100,54 @@ c         print *,"calling multibody_eello"
          call multibody_eello(ecorr,ecorr5,ecorr6,eturn6,n_corr,n_corr1)
 c         write (*,*) 'n_corr=',n_corr,' n_corr1=',n_corr1
 c         print *,ecorr,ecorr5,ecorr6,eturn6
+      else
+         ecorr=0.0d0
+         ecorr5=0.0d0
+         ecorr6=0.0d0
+         eturn6=0.0d0
       endif
       if (wcorr4.eq.0.0d0 .and. wcorr.gt.0.0d0) then
          call multibody_hb(ecorr,ecorr5,ecorr6,n_corr,n_corr1)
       endif
+
+      write (iout,*) "From Esaxs: Esaxs_constr",Esaxs_constr
+      if (nsaxs.gt.0 .and. saxs_mode.eq.0) then
+        call e_saxs(Esaxs_constr)
+        write (iout,*) "From Esaxs: Esaxs_constr",Esaxs_constr
+      else if (nsaxs.gt.0 .and. saxs_mode.gt.0) then
+        call e_saxsC(Esaxs_constr)
+c        write (iout,*) "From EsaxsC: Esaxs_constr",Esaxs_constr
+      else
+        Esaxs_constr = 0.0d0
+      endif
+
+c      write(iout,*) "TEST_ENE1 constr_homology=",constr_homology
+      if (constr_homology.ge.1) then
+        call e_modeller(ehomology_constr)
+      else
+        ehomology_constr=0.0d0
+      endif
+
+c      write(iout,*) "TEST_ENE1 ehomology_constr=",ehomology_constr
 c      write (iout,*) "ft(6)",fact(6)," evdw",evdw," evdw_t",evdw_t
 #ifdef SPLITELE
       etot=wsc*(evdw+fact(6)*evdw_t)+wscp*evdw2+welec*fact(1)*ees
      & +wvdwpp*evdw1
      & +wang*ebe+wtor*fact(1)*etors+wscloc*escloc
-     & +wstrain*ehpb+nss*ebr+wcorr*fact(3)*ecorr+wcorr5*fact(4)*ecorr5
+     & +wstrain*ehpb+wcorr*fact(3)*ecorr+wcorr5*fact(4)*ecorr5
      & +wcorr6*fact(5)*ecorr6+wturn4*fact(3)*eello_turn4
      & +wturn3*fact(2)*eello_turn3+wturn6*fact(5)*eturn6
      & +wel_loc*fact(2)*eel_loc+edihcnstr+wtor_d*fact(2)*etors_d
-     & +wbond*estr+wsccor*fact(1)*esccor
+     & +wbond*estr+wsccor*fact(1)*esccor+wsaxs*esaxs_constr
 #else
       etot=wsc*(evdw+fact(6)*evdw_t)+wscp*evdw2
      & +welec*fact(1)*(ees+evdw1)
      & +wang*ebe+wtor*fact(1)*etors+wscloc*escloc
-     & +wstrain*ehpb+nss*ebr+wcorr*fact(3)*ecorr+wcorr5*fact(4)*ecorr5
+     & +wstrain*ehpb+wcorr*fact(3)*ecorr+wcorr5*fact(4)*ecorr5
      & +wcorr6*fact(5)*ecorr6+wturn4*fact(3)*eello_turn4
      & +wturn3*fact(2)*eello_turn3+wturn6*fact(5)*eturn6
      & +wel_loc*fact(2)*eel_loc+edihcnstr+wtor_d*fact(2)*etors_d
-     & +wbond*estr+wsccor*fact(1)*esccor
+     & +wbond*estr+wsccor*fact(1)*esccor+wsaxs*esaxs_constr
 #endif
       energia(0)=etot
       energia(1)=evdw
@@ -154,6 +181,8 @@ c      write (iout,*) "ft(6)",fact(6)," evdw",evdw," evdw_t",evdw_t
       energia(19)=esccor
       energia(20)=edihcnstr
       energia(21)=evdw_t
+      energia(22)=ehomology_constr
+      energia(26)=esaxs_constr
 c detecting NaNQ
 #ifdef ISNAN
 #ifdef AIX
@@ -173,6 +202,11 @@ c detecting NaNQ
 #ifdef MPL
 c     endif
 #endif
+#define DEBUG
+#ifdef DEBUG
+      call enerprint(energia,fact)
+#endif
+#undef DEBUG
       if (calc_grad) then
 C
 C Sum up the components of the Cartesian gradient.
@@ -192,6 +226,7 @@ C
      &                wcorr6*fact(5)*gradcorr6(j,i)+
      &                wturn6*fact(5)*gcorr6_turn(j,i)+
      &                wsccor*fact(2)*gsccorc(j,i)
+     &               +wliptran*gliptranc(j,i)
           gradx(j,i,icg)=wsc*gvdwx(j,i)+wscp*gradx_scp(j,i)+
      &                  wbond*gradbx(j,i)+
      &                  wstrain*ghpbx(j,i)+wcorr*gradxorr(j,i)+
@@ -211,10 +246,12 @@ C
      &                wcorr6*fact(5)*gradcorr6(j,i)+
      &                wturn6*fact(5)*gcorr6_turn(j,i)+
      &                wsccor*fact(2)*gsccorc(j,i)
+     &               +wliptran*gliptranc(j,i)
           gradx(j,i,icg)=wsc*gvdwx(j,i)+wscp*gradx_scp(j,i)+
      &                  wbond*gradbx(j,i)+
      &                  wstrain*ghpbx(j,i)+wcorr*gradxorr(j,i)+
      &                  wsccor*fact(1)*gsccorx(j,i)
+     &                 +wliptran*gliptranx(j,i)
         enddo
 #endif
       enddo
@@ -228,9 +265,11 @@ C
      &   +wturn3*fact(2)*gel_loc_turn3(i)
      &   +wturn6*fact(5)*gel_loc_turn6(i)
      &   +wel_loc*fact(2)*gel_loc_loc(i)
-     &   +wsccor*fact(1)*gsccor_loc(i)
+c     &   +wsccor*fact(1)*gsccor_loc(i)
+c BYLA ROZNICA Z CLUSTER< OSTATNIA LINIA DODANA
       enddo
       endif
+      if (dyn_ss) call dyn_set_nss
       return
       end
 C------------------------------------------------------------------------
@@ -268,6 +307,8 @@ C------------------------------------------------------------------------
       esccor=energia(19)
       edihcnstr=energia(20)
       estr=energia(18)
+      ehomology_constr=energia(22)
+      esaxs_constr=energia(26)
 #ifdef SPLITELE
       write (iout,10) evdw,wsc,evdw2,wscp,ees,welec*fact(1),evdw1,
      &  wvdwpp,
@@ -276,7 +317,9 @@ C------------------------------------------------------------------------
      &  ecorr,wcorr*fact(3),ecorr5,wcorr5*fact(4),ecorr6,wcorr6*fact(5),
      &  eel_loc,wel_loc*fact(2),eello_turn3,wturn3*fact(2),
      &  eello_turn4,wturn4*fact(3),eello_turn6,wturn6*fact(5),
-     &  esccor,wsccor*fact(1),edihcnstr,ebr*nss,etot
+     &  esccor,wsccor*fact(1),edihcnstr,ehomology_constr,
+     &  esaxs_constr*wsaxs,ebr*nss,
+     &  etot
    10 format (/'Virtual-chain energies:'//
      & 'EVDW=  ',1pE16.6,' WEIGHT=',1pD16.6,' (SC-SC)'/
      & 'EVDW2= ',1pE16.6,' WEIGHT=',1pD16.6,' (SC-p)'/
@@ -298,6 +341,8 @@ C------------------------------------------------------------------------
      & 'ETURN6=',1pE16.6,' WEIGHT=',1pD16.6,' (turns, 6th order)'/
      & 'ESCCOR=',1pE16.6,' WEIGHT=',1pD16.6,' (backbone-rotamer corr)'/
      & 'EDIHC= ',1pE16.6,' (dihedral angle constraints)'/
+     & 'H_CONS=',1pE16.6,' (Homology model constraints energy)'/
+     & 'E_SAXS=',1pE16.6,' (SAXS restraints)'/
      & 'ESS=   ',1pE16.6,' (disulfide-bridge intrinsic energy)'/ 
      & 'ETOT=  ',1pE16.6,' (total)')
 #else
@@ -307,7 +352,8 @@ C------------------------------------------------------------------------
      &  ecorr6,wcorr6*fact(5),eel_loc,wel_loc*fact(2),
      &  eello_turn3,wturn3*fact(2),eello_turn4,wturn4*fact(3),
      &  eello_turn6,wturn6*fact(5),esccor*fact(1),wsccor,
-     &  edihcnstr,ebr*nss,etot
+     &  edihcnstr,ehomology_constr,esaxs_constr*wsaxs,ebr*nss,
+     &  etot
    10 format (/'Virtual-chain energies:'//
      & 'EVDW=  ',1pE16.6,' WEIGHT=',1pD16.6,' (SC-SC)'/
      & 'EVDW2= ',1pE16.6,' WEIGHT=',1pD16.6,' (SC-p)'/
@@ -328,6 +374,8 @@ C------------------------------------------------------------------------
      & 'ETURN6=',1pE16.6,' WEIGHT=',1pD16.6,' (turns, 6th order)'/
      & 'ESCCOR=',1pE16.6,' WEIGHT=',1pD16.6,' (backbone-rotamer corr)'/
      & 'EDIHC= ',1pE16.6,' (dihedral angle constraints)'/
+     & 'H_CONS=',1pE16.6,' (Homology model constraints energy)'/
+     & 'E_SAXS=',1pE16.6,' (SAXS restraints)'/
      & 'ESS=   ',1pE16.6,' (disulfide-bridge intrinsic energy)'/ 
      & 'ETOT=  ',1pE16.6,' (total)')
 #endif
@@ -368,9 +416,9 @@ cd    print *,'Entering ELJ nnt=',nnt,' nct=',nct,' expon=',expon
       evdw=0.0D0
       evdw_t=0.0d0
       do i=iatsc_s,iatsc_e
-        itypi=itype(i)
-        if (itypi.eq.21) cycle
-        itypi1=itype(i+1)
+        itypi=iabs(itype(i))
+        if (itypi.eq.ntyp1) cycle
+        itypi1=iabs(itype(i+1))
         xi=c(1,nres+i)
         yi=c(2,nres+i)
         zi=c(3,nres+i)
@@ -383,8 +431,8 @@ C
 cd        write (iout,*) 'i=',i,' iint=',iint,' istart=',istart(i,iint),
 cd   &                  'iend=',iend(i,iint)
           do j=istart(i,iint),iend(i,iint)
-            itypj=itype(j)
-            if (itypj.eq.21) cycle
+            itypj=iabs(itype(j))
+            if (itypj.eq.ntyp1) cycle
             xj=c(1,nres+j)-xi
             yj=c(2,nres+j)-yi
             zj=c(3,nres+j)-zi
@@ -394,8 +442,8 @@ C Change 12/1/95 to calculate four-body interactions
 c           write (iout,*)'i=',i,' j=',j,' itypi=',itypi,' itypj=',itypj
             eps0ij=eps(itypi,itypj)
             fac=rrij**expon2
-            e1=fac*fac*aa(itypi,itypj)
-            e2=fac*bb(itypi,itypj)
+            e1=fac*fac*aa
+            e2=fac*bb
             evdwij=e1+e2
             ij=icant(itypi,itypj)
             eneps_temp(1,ij)=eneps_temp(1,ij)+e1/dabs(eps0ij)
@@ -406,7 +454,7 @@ cd          write (iout,'(2(a3,i3,2x),6(1pd12.4)/2(3(1pd12.4),5x)/)')
 cd   &        restyp(itypi),i,restyp(itypj),j,aa(itypi,itypj),
 cd   &        bb(itypi,itypj),1.0D0/dsqrt(rrij),evdwij,epsi,sigm,
 cd   &        (c(k,i),k=1,3),(c(k,j),k=1,3)
-            if (bb(itypi,itypj).gt.0.0d0) then
+            if (bb.gt.0.0d0) then
               evdw=evdw+evdwij
             else
               evdw_t=evdw_t+evdwij
@@ -541,9 +589,9 @@ c     print *,'Entering ELJK nnt=',nnt,' nct=',nct,' expon=',expon
       evdw=0.0D0
       evdw_t=0.0d0
       do i=iatsc_s,iatsc_e
-        itypi=itype(i)
-        if (itypi.eq.21) cycle
-        itypi1=itype(i+1)
+        itypi=iabs(itype(i))
+        if (itypi.eq.ntyp1) cycle
+        itypi1=iabs(itype(i+1))
         xi=c(1,nres+i)
         yi=c(2,nres+i)
         zi=c(3,nres+i)
@@ -552,8 +600,8 @@ C Calculate SC interaction energy.
 C
         do iint=1,nint_gr(i)
           do j=istart(i,iint),iend(i,iint)
-            itypj=itype(j)
-            if (itypj.eq.21) cycle
+            itypj=iabs(itype(j))
+            if (itypj.eq.ntyp1) cycle
             xj=c(1,nres+j)-xi
             yj=c(2,nres+j)-yi
             zj=c(3,nres+j)-zi
@@ -564,8 +612,8 @@ C
             rij=1.0D0/r_inv_ij 
             r_shift_inv=1.0D0/(rij+r0(itypi,itypj)-sigma(itypi,itypj))
             fac=r_shift_inv**expon
-            e1=fac*fac*aa(itypi,itypj)
-            e2=fac*bb(itypi,itypj)
+            e1=fac*fac*aa
+            e2=fac*bb
             evdwij=e_augm+e1+e2
             ij=icant(itypi,itypj)
             eneps_temp(1,ij)=eneps_temp(1,ij)+(e1+a_augm)
@@ -578,7 +626,7 @@ cd   &        restyp(itypi),i,restyp(itypj),j,aa(itypi,itypj),
 cd   &        bb(itypi,itypj),augm(itypi,itypj),epsi,sigm,
 cd   &        sigma(itypi,itypj),1.0D0/dsqrt(rrij),evdwij,
 cd   &        (c(k,i),k=1,3),(c(k,j),k=1,3)
-            if (bb(itypi,itypj).gt.0.0d0) then
+            if (bb.gt.0.0d0) then
               evdw=evdw+evdwij
             else 
               evdw_t=evdw_t+evdwij
@@ -654,9 +702,9 @@ c     else
 c     endif
       ind=0
       do i=iatsc_s,iatsc_e
-        itypi=itype(i)
-        if (itypi.eq.21) cycle
-        itypi1=itype(i+1)
+        itypi=iabs(itype(i))
+        if (itypi.eq.ntyp1) cycle
+        itypi1=iabs(itype(i+1))
         xi=c(1,nres+i)
         yi=c(2,nres+i)
         zi=c(3,nres+i)
@@ -670,8 +718,8 @@ C
         do iint=1,nint_gr(i)
           do j=istart(i,iint),iend(i,iint)
             ind=ind+1
-            itypj=itype(j)
-            if (itypj.eq.21) cycle
+            itypj=iabs(itype(j))
+            if (itypj.eq.ntyp1) cycle
             dscj_inv=vbld_inv(j+nres)
             chi1=chi(itypi,itypj)
             chi2=chi(itypj,itypi)
@@ -710,8 +758,8 @@ C Calculate the angle-dependent terms of energy & contributions to derivatives.
 C Calculate whole angle-dependent part of epsilon and contributions
 C to its derivatives
             fac=(rrij*sigsq)**expon2
-            e1=fac*fac*aa(itypi,itypj)
-            e2=fac*bb(itypi,itypj)
+            e1=fac*fac*aa
+            e2=fac*bb
             evdwij=eps1*eps2rt*eps3rt*(e1+e2)
             eps2der=evdwij*eps3rt
             eps3der=evdwij*eps2rt
@@ -721,15 +769,15 @@ C to its derivatives
             eneps_temp(1,ij)=eneps_temp(1,ij)+e1*aux
      &        /dabs(eps(itypi,itypj))
             eneps_temp(2,ij)=eneps_temp(2,ij)+e2*aux/eps(itypi,itypj)
-            if (bb(itypi,itypj).gt.0.0d0) then
+            if (bb.gt.0.0d0) then
               evdw=evdw+evdwij
             else
               evdw_t=evdw_t+evdwij
             endif
             if (calc_grad) then
             if (lprn) then
-            sigm=dabs(aa(itypi,itypj)/bb(itypi,itypj))**(1.0D0/6.0D0)
-            epsi=bb(itypi,itypj)**2/aa(itypi,itypj)
+            sigm=dabs(aa/bb)**(1.0D0/6.0D0)
+            epsi=bb**2/aa
             write (iout,'(2(a3,i3,2x),15(0pf7.3))')
      &        restyp(itypi),i,restyp(itypj),j,
      &        epsi,sigm,chi1,chi2,chip1,chip2,
@@ -776,9 +824,10 @@ C
       include 'COMMON.ENEPS'
       include 'COMMON.IOUNITS'
       include 'COMMON.CALC'
+      include 'COMMON.SBRIDGE'
       logical lprn
       common /srutu/icall
-      integer icant
+      integer icant,xshift,yshift,zshift
       external icant
       do i=1,210
         do j=1,2
@@ -792,12 +841,42 @@ c     print *,'Entering EGB nnt=',nnt,' nct=',nct,' expon=',expon
 c      if (icall.gt.0) lprn=.true.
       ind=0
       do i=iatsc_s,iatsc_e
-        itypi=itype(i)
-        if (itypi.eq.21) cycle
-        itypi1=itype(i+1)
+        itypi=iabs(itype(i))
+        if (itypi.eq.ntyp1) cycle
+        itypi1=iabs(itype(i+1))
         xi=c(1,nres+i)
         yi=c(2,nres+i)
         zi=c(3,nres+i)
+C returning the ith atom to box
+          xi=mod(xi,boxxsize)
+          if (xi.lt.0) xi=xi+boxxsize
+          yi=mod(yi,boxysize)
+          if (yi.lt.0) yi=yi+boxysize
+          zi=mod(zi,boxzsize)
+          if (zi.lt.0) zi=zi+boxzsize
+       if ((zi.gt.bordlipbot)
+     &.and.(zi.lt.bordliptop)) then
+C the energy transfer exist
+        if (zi.lt.buflipbot) then
+C what fraction I am in
+         fracinbuf=1.0d0-
+     &        ((zi-bordlipbot)/lipbufthick)
+C lipbufthick is thickenes of lipid buffore
+         sslipi=sscalelip(fracinbuf)
+         ssgradlipi=-sscagradlip(fracinbuf)/lipbufthick
+        elseif (zi.gt.bufliptop) then
+         fracinbuf=1.0d0-((bordliptop-zi)/lipbufthick)
+         sslipi=sscalelip(fracinbuf)
+         ssgradlipi=sscagradlip(fracinbuf)/lipbufthick
+        else
+         sslipi=1.0d0
+         ssgradlipi=0.0
+        endif
+       else
+         sslipi=0.0d0
+         ssgradlipi=0.0
+       endif
+
         dxi=dc_norm(1,nres+i)
         dyi=dc_norm(2,nres+i)
         dzi=dc_norm(3,nres+i)
@@ -807,9 +886,29 @@ C Calculate SC interaction energy.
 C
         do iint=1,nint_gr(i)
           do j=istart(i,iint),iend(i,iint)
+            IF (dyn_ss_mask(i).and.dyn_ss_mask(j)) THEN
+              call dyn_ssbond_ene(i,j,evdwij)
+              evdw=evdw+evdwij
+C            write (iout,'(a6,2i5,0pf7.3,a3,2f10.3)')
+C     &                        'evdw',i,j,evdwij,' ss',evdw,evdw_t
+C triple bond artifac removal
+             do k=j+1,iend(i,iint)
+C search over all next residues
+              if (dyn_ss_mask(k)) then
+C check if they are cysteins
+C              write(iout,*) 'k=',k
+              call triple_ssbond_ene(i,j,k,evdwij)
+C call the energy function that removes the artifical triple disulfide
+C bond the soubroutine is located in ssMD.F
+              evdw=evdw+evdwij
+C             write (iout,'(a6,2i5,0pf7.3,a3,2f10.3)')
+C     &                        'evdw',i,j,evdwij,'tss',evdw,evdw_t
+              endif!dyn_ss_mask(k)
+             enddo! k
+            ELSE
             ind=ind+1
-            itypj=itype(j)
-            if (itypj.eq.21) cycle
+            itypj=iabs(itype(j))
+            if (itypj.eq.ntyp1) cycle
             dscj_inv=vbld_inv(j+nres)
             sig0ij=sigma(itypi,itypj)
             chi1=chi(itypi,itypj)
@@ -831,17 +930,96 @@ c           chip12=0.0D0
 c           alf1=0.0D0
 c           alf2=0.0D0
 c           alf12=0.0D0
-            xj=c(1,nres+j)-xi
-            yj=c(2,nres+j)-yi
-            zj=c(3,nres+j)-zi
+            xj=c(1,nres+j)
+            yj=c(2,nres+j)
+            zj=c(3,nres+j)
+C returning jth atom to box
+          xj=mod(xj,boxxsize)
+          if (xj.lt.0) xj=xj+boxxsize
+          yj=mod(yj,boxysize)
+          if (yj.lt.0) yj=yj+boxysize
+          zj=mod(zj,boxzsize)
+          if (zj.lt.0) zj=zj+boxzsize
+       if ((zj.gt.bordlipbot)
+     &.and.(zj.lt.bordliptop)) then
+C the energy transfer exist
+        if (zj.lt.buflipbot) then
+C what fraction I am in
+         fracinbuf=1.0d0-
+     &        ((zj-bordlipbot)/lipbufthick)
+C lipbufthick is thickenes of lipid buffore
+         sslipj=sscalelip(fracinbuf)
+         ssgradlipj=-sscagradlip(fracinbuf)/lipbufthick
+        elseif (zj.gt.bufliptop) then
+         fracinbuf=1.0d0-((bordliptop-zj)/lipbufthick)
+         sslipj=sscalelip(fracinbuf)
+         ssgradlipj=sscagradlip(fracinbuf)/lipbufthick
+        else
+         sslipj=1.0d0
+         ssgradlipj=0.0
+        endif
+       else
+         sslipj=0.0d0
+         ssgradlipj=0.0
+       endif
+      aa=aa_lip(itypi,itypj)*(sslipi+sslipj)/2.0d0
+     &  +aa_aq(itypi,itypj)*(2.0d0-sslipi-sslipj)/2.0d0
+      bb=bb_lip(itypi,itypj)*(sslipi+sslipj)/2.0d0
+     &  +bb_aq(itypi,itypj)*(2.0d0-sslipi-sslipj)/2.0d0
+C       if (aa.ne.aa_aq(itypi,itypj)) then
+       
+C      write(iout,*) "tu,", i,j,aa_aq(itypi,itypj)-aa,
+C     & bb_aq(itypi,itypj)-bb,
+C     & sslipi,sslipj
+C         endif
+
+C        write(iout,*),aa,aa_lip(itypi,itypj),aa_aq(itypi,itypj)
+C checking the distance
+      dist_init=(xj-xi)**2+(yj-yi)**2+(zj-zi)**2
+      xj_safe=xj
+      yj_safe=yj
+      zj_safe=zj
+      subchap=0
+C finding the closest
+      do xshift=-1,1
+      do yshift=-1,1
+      do zshift=-1,1
+          xj=xj_safe+xshift*boxxsize
+          yj=yj_safe+yshift*boxysize
+          zj=zj_safe+zshift*boxzsize
+          dist_temp=(xj-xi)**2+(yj-yi)**2+(zj-zi)**2
+          if(dist_temp.lt.dist_init) then
+            dist_init=dist_temp
+            xj_temp=xj
+            yj_temp=yj
+            zj_temp=zj
+            subchap=1
+          endif
+       enddo
+       enddo
+       enddo
+       if (subchap.eq.1) then
+          xj=xj_temp-xi
+          yj=yj_temp-yi
+          zj=zj_temp-zi
+       else
+          xj=xj_safe-xi
+          yj=yj_safe-yi
+          zj=zj_safe-zi
+       endif
+
             dxj=dc_norm(1,nres+j)
             dyj=dc_norm(2,nres+j)
             dzj=dc_norm(3,nres+j)
 c            write (iout,*) i,j,xj,yj,zj
             rrij=1.0D0/(xj*xj+yj*yj+zj*zj)
             rij=dsqrt(rrij)
+            sss=sscale((1.0d0/rij)/sigma(itypi,itypj))
+            sssgrad=sscagrad((1.0d0/rij)/sigma(itypi,itypj))
+            if (sss.le.0.0) cycle
 C Calculate angle-dependent terms of energy and contributions to their
 C derivatives.
+
             call sc_angular
             sigsq=1.0D0/sigsq
             sig=sig0ij*dsqrt(sigsq)
@@ -855,16 +1033,16 @@ C I hate to put IF's in the loops, but here don't have another choice!!!!
 c---------------------------------------------------------------
             rij_shift=1.0D0/rij_shift 
             fac=rij_shift**expon
-            e1=fac*fac*aa(itypi,itypj)
-            e2=fac*bb(itypi,itypj)
+            e1=fac*fac*aa
+            e2=fac*bb
             evdwij=eps1*eps2rt*eps3rt*(e1+e2)
             eps2der=evdwij*eps3rt
             eps3der=evdwij*eps2rt
             evdwij=evdwij*eps2rt*eps3rt
-            if (bb(itypi,itypj).gt.0) then
-              evdw=evdw+evdwij
+            if (bb.gt.0) then
+              evdw=evdw+evdwij*sss
             else
-              evdw_t=evdw_t+evdwij
+              evdw_t=evdw_t+evdwij*sss
             endif
             ij=icant(itypi,itypj)
             aux=eps1*eps2rt**2*eps3rt**2
@@ -875,8 +1053,9 @@ c            write (iout,*) "i",i," j",j," itypi",itypi," itypj",itypj,
 c     &         " ij",ij," eneps",aux*e1/dabs(eps(itypi,itypj)),
 c     &         aux*e2/eps(itypi,itypj)
 c            if (lprn) then
-            sigm=dabs(aa(itypi,itypj)/bb(itypi,itypj))**(1.0D0/6.0D0)
-            epsi=bb(itypi,itypj)**2/aa(itypi,itypj)
+            sigm=dabs(aa/bb)**(1.0D0/6.0D0)
+            epsi=bb**2/aa
+C#define DEBUG
 #ifdef DEBUG
             write (iout,'(2(a3,i3,2x),17(0pf7.3))')
      &        restyp(itypi),i,restyp(itypj),j,
@@ -886,6 +1065,7 @@ c            if (lprn) then
      &        evdwij
              write (iout,*) "partial sum", evdw, evdw_t
 #endif
+C#undef DEBUG
 c            endif
             if (calc_grad) then
 C Calculate gradient components.
@@ -893,6 +1073,7 @@ C Calculate gradient components.
             fac=-expon*(e1+evdwij)*rij_shift
             sigder=fac*sigder
             fac=rij*fac
+            fac=fac+evdwij/sss*sssgrad/sigma(itypi,itypj)*rij
 C Calculate the radial part of the gradient
             gg(1)=xj*fac
             gg(2)=yj*fac
@@ -900,6 +1081,8 @@ C Calculate the radial part of the gradient
 C Calculate angular part of the gradient.
             call sc_grad
             endif
+C            write(iout,*)  "partial sum", evdw, evdw_t
+            ENDIF    ! dyn_ss            
           enddo      ! j
         enddo        ! iint
       enddo          ! i
@@ -942,9 +1125,9 @@ c     print *,'Entering EGB nnt=',nnt,' nct=',nct,' expon=',expon
 c      if (icall.gt.0) lprn=.true.
       ind=0
       do i=iatsc_s,iatsc_e
-        itypi=itype(i)
-        if (itypi.eq.21) cycle
-        itypi1=itype(i+1)
+        itypi=iabs(itype(i))
+        if (itypi.eq.ntyp1) cycle
+        itypi1=iabs(itype(i+1))
         xi=c(1,nres+i)
         yi=c(2,nres+i)
         zi=c(3,nres+i)
@@ -958,8 +1141,8 @@ C
         do iint=1,nint_gr(i)
           do j=istart(i,iint),iend(i,iint)
             ind=ind+1
-            itypj=itype(j)
-            if (itypj.eq.21) cycle
+            itypj=iabs(itype(j))
+            if (itypj.eq.ntyp1) cycle
             dscj_inv=vbld_inv(j+nres)
             sig0ij=sigma(itypi,itypj)
             r0ij=r0(itypi,itypj)
@@ -1005,15 +1188,15 @@ C I hate to put IF's in the loops, but here don't have another choice!!!!
 c---------------------------------------------------------------
             rij_shift=1.0D0/rij_shift 
             fac=rij_shift**expon
-            e1=fac*fac*aa(itypi,itypj)
-            e2=fac*bb(itypi,itypj)
+            e1=fac*fac*aa
+            e2=fac*bb
             evdwij=eps1*eps2rt*eps3rt*(e1+e2)
             eps2der=evdwij*eps3rt
             eps3der=evdwij*eps2rt
             fac_augm=rrij**expon
             e_augm=augm(itypi,itypj)*fac_augm
             evdwij=evdwij*eps2rt*eps3rt
-            if (bb(itypi,itypj).gt.0.0d0) then
+            if (bb.gt.0.0d0) then
               evdw=evdw+evdwij+e_augm
             else
               evdw_t=evdw_t+evdwij+e_augm
@@ -1771,6 +1954,7 @@ C
       implicit real*8 (a-h,o-z)
       include 'DIMENSIONS'
       include 'DIMENSIONS.ZSCOPT'
+      include 'DIMENSIONS.FREE'
       include 'COMMON.CONTROL'
       include 'COMMON.IOUNITS'
       include 'COMMON.GEO'
@@ -1853,7 +2037,14 @@ cd      write (iout,*) 'iatel_s=',iatel_s,' iatel_e=',iatel_e
         gcorr_loc(i)=0.0d0
       enddo
       do i=iatel_s,iatel_e
-        if (itype(i).eq.21 .or. itype(i+1).eq.21) cycle
+cAna           if (i.le.1) cycle
+           if (itype(i).eq.ntyp1.or. itype(i+1).eq.ntyp1
+cAna     &  .or. ((i+2).gt.nres)
+cAna     &  .or. ((i-1).le.0)
+cAna     &  .or. itype(i+2).eq.ntyp1
+cAna     &  .or. itype(i-1).eq.ntyp1
+     &) cycle
+C         endif
         if (itel(i).eq.0) goto 1215
         dxi=dc(1,i)
         dyi=dc(2,i)
@@ -1864,10 +2055,22 @@ cd      write (iout,*) 'iatel_s=',iatel_s,' iatel_e=',iatel_e
         xmedi=c(1,i)+0.5d0*dxi
         ymedi=c(2,i)+0.5d0*dyi
         zmedi=c(3,i)+0.5d0*dzi
+          xmedi=mod(xmedi,boxxsize)
+          if (xmedi.lt.0) xmedi=xmedi+boxxsize
+          ymedi=mod(ymedi,boxysize)
+          if (ymedi.lt.0) ymedi=ymedi+boxysize
+          zmedi=mod(zmedi,boxzsize)
+          if (zmedi.lt.0) zmedi=zmedi+boxzsize
         num_conti=0
-c        write (iout,*) 'i',i,' ielstart',ielstart(i),' ielend',ielend(i)
+C        write (iout,*) 'i',i,' ielstart',ielstart(i),' ielend',ielend(i)
         do j=ielstart(i),ielend(i)
-          if (itype(j).eq.21 .or. itype(j+1).eq.21) cycle
+cAna          if (j.le.1) cycle
+          if (itype(j).eq.ntyp1 .or. itype(j+1).eq.ntyp1
+cAna     & .or.((j+2).gt.nres)
+cAna     & .or.((j-1).le.0)
+cAna     & .or.itype(j+2).eq.ntyp1
+cAna     & .or.itype(j-1).eq.ntyp1
+     &) cycle
           if (itel(j).eq.0) goto 1216
           ind=ind+1
           iteli=itel(i)
@@ -1889,10 +2092,49 @@ C End diagnostics
           dx_normj=dc_norm(1,j)
           dy_normj=dc_norm(2,j)
           dz_normj=dc_norm(3,j)
-          xj=c(1,j)+0.5D0*dxj-xmedi
-          yj=c(2,j)+0.5D0*dyj-ymedi
-          zj=c(3,j)+0.5D0*dzj-zmedi
+          xj=c(1,j)+0.5D0*dxj
+          yj=c(2,j)+0.5D0*dyj
+          zj=c(3,j)+0.5D0*dzj
+         xj=mod(xj,boxxsize)
+          if (xj.lt.0) xj=xj+boxxsize
+          yj=mod(yj,boxysize)
+          if (yj.lt.0) yj=yj+boxysize
+          zj=mod(zj,boxzsize)
+          if (zj.lt.0) zj=zj+boxzsize
+      dist_init=(xj-xmedi)**2+(yj-ymedi)**2+(zj-zmedi)**2
+      xj_safe=xj
+      yj_safe=yj
+      zj_safe=zj
+      isubchap=0
+      do xshift=-1,1
+      do yshift=-1,1
+      do zshift=-1,1
+          xj=xj_safe+xshift*boxxsize
+          yj=yj_safe+yshift*boxysize
+          zj=zj_safe+zshift*boxzsize
+          dist_temp=(xj-xmedi)**2+(yj-ymedi)**2+(zj-zmedi)**2
+          if(dist_temp.lt.dist_init) then
+            dist_init=dist_temp
+            xj_temp=xj
+            yj_temp=yj
+            zj_temp=zj
+            isubchap=1
+          endif
+       enddo
+       enddo
+       enddo
+       if (isubchap.eq.1) then
+          xj=xj_temp-xmedi
+          yj=yj_temp-ymedi
+          zj=zj_temp-zmedi
+       else
+          xj=xj_safe-xmedi
+          yj=yj_safe-ymedi
+          zj=zj_safe-zmedi
+       endif
           rij=xj*xj+yj*yj+zj*zj
+            sss=sscale(sqrt(rij))
+            sssgrad=sscagrad(sqrt(rij))
           rrmij=1.0D0/rij
           rij=dsqrt(rij)
           rmij=1.0D0/rij
@@ -1916,7 +2158,7 @@ c          write (iout,*) "i",i,iteli," j",j,itelj," eesij",eesij
 C 12/26/95 - for the evaluation of multi-body H-bonding interactions
           ees0ij=4.0D0+fac*fac-3.0D0*(cosb*cosb+cosg*cosg)
           ees=ees+eesij
-          evdw1=evdw1+evdwij
+          evdw1=evdw1+evdwij*sss
 cd          write(iout,'(2(2i3,2x),7(1pd12.4)/2(3(1pd12.4),5x)/)')
 cd     &      iteli,i,itelj,j,aaa,bbb,ael6i,ael3i,
 cd     &      1.0D0/dsqrt(rrmij),evdwij,eesij,
@@ -1925,7 +2167,7 @@ C
 C Calculate contributions to the Cartesian gradient.
 C
 #ifdef SPLITELE
-          facvdw=-6*rrmij*(ev1+evdwij) 
+          facvdw=-6*rrmij*(ev1+evdwij)*sss
           facel=-3*rrmij*(el1+eesij)
           fac1=fac
           erij(1)=xj*rmij
@@ -2541,6 +2783,18 @@ C Third- and fourth-order contributions from turns
      &    aggj(3,4),aggj1(3,4),a_temp(2,2)
       common /locel/ a_temp,agg,aggi,aggi1,aggj,aggj1,j1,j2
       if (j.eq.i+2) then
+      if (itype(i).eq.ntyp1 .or. itype(i+1).eq.ntyp1
+C changes suggested by Ana to avoid out of bounds
+C     & .or.((i+5).gt.nres)
+C     & .or.((i-1).le.0)
+C end of changes suggested by Ana
+     &    .or. itype(i+2).eq.ntyp1
+     &    .or. itype(i+3).eq.ntyp1
+C     &    .or. itype(i+5).eq.ntyp1
+C     &    .or. itype(i).eq.ntyp1
+C     &    .or. itype(i-1).eq.ntyp1
+     &    ) goto 179
+
 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
 C
 C               Third-order contributions
@@ -2603,7 +2857,19 @@ C Cartesian derivatives
      &      +0.5d0*(pizda(1,1)+pizda(2,2))
         enddo
         endif
-      else if (j.eq.i+3 .and. itype(i+2).ne.21) then
+  179 continue
+      else if (j.eq.i+3 .and. itype(i+2).ne.ntyp1) then
+      if (itype(i).eq.ntyp1 .or. itype(i+1).eq.ntyp1
+C changes suggested by Ana to avoid out of bounds
+C     & .or.((i+5).gt.nres)
+C     & .or.((i-1).le.0)
+C end of changes suggested by Ana
+     &    .or. itype(i+3).eq.ntyp1
+     &    .or. itype(i+4).eq.ntyp1
+C     &    .or. itype(i+5).eq.ntyp1
+     &    .or. itype(i).eq.ntyp1
+C     &    .or. itype(i-1).eq.ntyp1
+     &    ) goto 178
 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
 C
 C               Fourth-order contributions
@@ -2743,6 +3009,7 @@ C Remaining derivatives of this turn contribution
           gcorr4_turn(l,j1)=gcorr4_turn(l,j1)-(s1+s2+s3)
         enddo
         endif
+ 178  continue
       endif          
       return
       end
@@ -2804,7 +3071,7 @@ cd    print '(a)','Enter ESCP'
 c      write (iout,*) 'iatscp_s=',iatscp_s,' iatscp_e=',iatscp_e,
 c     &  ' scal14',scal14
       do i=iatscp_s,iatscp_e
-        if (itype(i).eq.21 .or. itype(i+1).eq.21) cycle
+        if (itype(i).eq.ntyp1 .or. itype(i+1).eq.ntyp1) cycle
         iteli=itel(i)
 c        write (iout,*) "i",i," iteli",iteli," nscp_gr",nscp_gr(i),
 c     &   " iscp",(iscpstart(i,j),iscpend(i,j),j=1,nscp_gr(i))
@@ -2812,37 +3079,90 @@ c     &   " iscp",(iscpstart(i,j),iscpend(i,j),j=1,nscp_gr(i))
         xi=0.5D0*(c(1,i)+c(1,i+1))
         yi=0.5D0*(c(2,i)+c(2,i+1))
         zi=0.5D0*(c(3,i)+c(3,i+1))
-
+C Returning the ith atom to box
+          xi=mod(xi,boxxsize)
+          if (xi.lt.0) xi=xi+boxxsize
+          yi=mod(yi,boxysize)
+          if (yi.lt.0) yi=yi+boxysize
+          zi=mod(zi,boxzsize)
+          if (zi.lt.0) zi=zi+boxzsize
         do iint=1,nscp_gr(i)
 
         do j=iscpstart(i,iint),iscpend(i,iint)
-          itypj=itype(j)
-          if (itypj.eq.21) cycle
+          itypj=iabs(itype(j))
+          if (itypj.eq.ntyp1) cycle
 C Uncomment following three lines for SC-p interactions
 c         xj=c(1,nres+j)-xi
 c         yj=c(2,nres+j)-yi
 c         zj=c(3,nres+j)-zi
 C Uncomment following three lines for Ca-p interactions
-          xj=c(1,j)-xi
-          yj=c(2,j)-yi
-          zj=c(3,j)-zi
+          xj=c(1,j)
+          yj=c(2,j)
+          zj=c(3,j)
+C returning the jth atom to box
+          xj=mod(xj,boxxsize)
+          if (xj.lt.0) xj=xj+boxxsize
+          yj=mod(yj,boxysize)
+          if (yj.lt.0) yj=yj+boxysize
+          zj=mod(zj,boxzsize)
+          if (zj.lt.0) zj=zj+boxzsize
+      dist_init=(xj-xi)**2+(yj-yi)**2+(zj-zi)**2
+      xj_safe=xj
+      yj_safe=yj
+      zj_safe=zj
+      subchap=0
+C Finding the closest jth atom
+      do xshift=-1,1
+      do yshift=-1,1
+      do zshift=-1,1
+          xj=xj_safe+xshift*boxxsize
+          yj=yj_safe+yshift*boxysize
+          zj=zj_safe+zshift*boxzsize
+          dist_temp=(xj-xi)**2+(yj-yi)**2+(zj-zi)**2
+          if(dist_temp.lt.dist_init) then
+            dist_init=dist_temp
+            xj_temp=xj
+            yj_temp=yj
+            zj_temp=zj
+            subchap=1
+          endif
+       enddo
+       enddo
+       enddo
+       if (subchap.eq.1) then
+          xj=xj_temp-xi
+          yj=yj_temp-yi
+          zj=zj_temp-zi
+       else
+          xj=xj_safe-xi
+          yj=yj_safe-yi
+          zj=zj_safe-zi
+       endif
           rrij=1.0D0/(xj*xj+yj*yj+zj*zj)
+C sss is scaling function for smoothing the cutoff gradient otherwise
+C the gradient would not be continuouse
+          sss=sscale(1.0d0/(dsqrt(rrij)))
+          if (sss.le.0.0d0) cycle
+          sssgrad=sscagrad(1.0d0/(dsqrt(rrij)))
           fac=rrij**expon2
           e1=fac*fac*aad(itypj,iteli)
           e2=fac*bad(itypj,iteli)
           if (iabs(j-i) .le. 2) then
             e1=scal14*e1
             e2=scal14*e2
-            evdw2_14=evdw2_14+e1+e2
+            evdw2_14=evdw2_14+(e1+e2)*sss
           endif
           evdwij=e1+e2
-c          write (iout,*) i,j,evdwij
-          evdw2=evdw2+evdwij
+c          write (iout,'(a6,2i5,0pf7.3,2i3,3e11.3)')
+c     &        'evdw2',i,j,evdwij,iteli,itypj,fac,aad(itypj,iteli),
+c     &       bad(itypj,iteli)
+          evdw2=evdw2+evdwij*sss
           if (calc_grad) then
 C
 C Calculate contributions to the gradient in the virtual-bond and SC vectors.
 C
-          fac=-(evdwij+e1)*rrij
+          fac=-(evdwij+e1)*rrij*sss
+          fac=fac+(evdwij)*sssgrad*dsqrt(rrij)/expon
           ggg(1)=xj*fac
           ggg(2)=yj*fac
           ggg(3)=zj*fac
       implicit real*8 (a-h,o-z)
       include 'DIMENSIONS'
       include 'DIMENSIONS.ZSCOPT'
+      include 'DIMENSIONS.FREE'
       include 'COMMON.SBRIDGE'
       include 'COMMON.CHAIN'
       include 'COMMON.DERIV'
       include 'COMMON.VAR'
       include 'COMMON.INTERACT'
+      include 'COMMON.CONTROL'
+      include 'COMMON.IOUNITS'
       dimension ggg(3)
       ehpb=0.0D0
 cd    print *,'edis: nhpb=',nhpb,' fbr=',fbr
 cd    print *,'link_start=',link_start,' link_end=',link_end
+C      write(iout,*) link_end, "link_end"
       if (link_end.eq.0) return
       do i=link_start,link_end
 C If ihpb(i) and jhpb(i) > NRES, this is a SC-SC distance, otherwise a
@@ -2927,24 +3251,98 @@ C iii and jjj point to the residues for which the distance is assigned.
         endif
 C 24/11/03 AL: SS bridges handled separately because of introducing a specific
 C    distance and angle dependent SS bond potential.
-        if (ii.gt.nres .and. itype(iii).eq.1 .and. itype(jjj).eq.1) then
+C        if (ii.gt.nres .and. iabs(itype(iii)).eq.1 .and. 
+C     & iabs(itype(jjj)).eq.1) then
+C       write(iout,*) constr_dist,"const"
+       if (.not.dyn_ss .and. i.le.nss) then
+         if (ii.gt.nres .and. iabs(itype(iii)).eq.1 .and.
+     & iabs(itype(jjj)).eq.1) then
           call ssbond_ene(iii,jjj,eij)
           ehpb=ehpb+2*eij
-        else
-C Calculate the distance between the two points and its difference from the
-C target distance.
-        dd=dist(ii,jj)
-        rdis=dd-dhpb(i)
+           endif !ii.gt.neres
+        else if (ii.gt.nres .and. jj.gt.nres) then
+c Restraints from contact prediction
+          dd=dist(ii,jj)
+          if (constr_dist.eq.11) then
+C            ehpb=ehpb+fordepth(i)**4.0d0
+C     &          *rlornmr1(dd,dhpb(i),dhpb1(i),forcon(i))
+            ehpb=ehpb+fordepth(i)**4.0d0
+     &          *rlornmr1(dd,dhpb(i),dhpb1(i),forcon(i))
+            fac=fordepth(i)**4.0d0
+     &          *rlornmr1prim(dd,dhpb(i),dhpb1(i),forcon(i))/dd
+C          write (iout,'(a6,2i5,3f8.3)') "edisl",ii,jj,
+C     &    ehpb,fordepth(i),dd
+C            write(iout,*) ehpb,"atu?"
+C            ehpb,"tu?"
+C            fac=fordepth(i)**4.0d0
+C     &          *rlornmr1prim(dd,dhpb(i),dhpb1(i),forcon(i))/dd
+           else
+          if (dhpb1(i).gt.0.0d0) then
+            ehpb=ehpb+2*forcon(i)*gnmr1(dd,dhpb(i),dhpb1(i))
+            fac=forcon(i)*gnmr1prim(dd,dhpb(i),dhpb1(i))/dd
+c            write (iout,*) "beta nmr",
+c     &        dd,2*forcon(i)*gnmr1(dd,dhpb(i),dhpb1(i))
+          else
+            dd=dist(ii,jj)
+            rdis=dd-dhpb(i)
 C Get the force constant corresponding to this distance.
-        waga=forcon(i)
+            waga=forcon(i)
 C Calculate the contribution to energy.
-        ehpb=ehpb+waga*rdis*rdis
+            ehpb=ehpb+waga*rdis*rdis
+c            write (iout,*) "beta reg",dd,waga*rdis*rdis
 C
 C Evaluate gradient.
 C
-        fac=waga*rdis/dd
-cd      print *,'i=',i,' ii=',ii,' jj=',jj,' dhpb=',dhpb(i),' dd=',dd,
-cd   &   ' waga=',waga,' fac=',fac
+            fac=waga*rdis/dd
+          endif !end dhpb1(i).gt.0
+          endif !end const_dist=11
+          do j=1,3
+            ggg(j)=fac*(c(j,jj)-c(j,ii))
+          enddo
+          do j=1,3
+            ghpbx(j,iii)=ghpbx(j,iii)-ggg(j)
+            ghpbx(j,jjj)=ghpbx(j,jjj)+ggg(j)
+          enddo
+          do k=1,3
+            ghpbc(k,jjj)=ghpbc(k,jjj)+ggg(k)
+            ghpbc(k,iii)=ghpbc(k,iii)-ggg(k)
+          enddo
+        else !ii.gt.nres
+C          write(iout,*) "before"
+          dd=dist(ii,jj)
+C          write(iout,*) "after",dd
+          if (constr_dist.eq.11) then
+            ehpb=ehpb+fordepth(i)**4.0d0
+     &          *rlornmr1(dd,dhpb(i),dhpb1(i),forcon(i))
+            fac=fordepth(i)**4.0d0
+     &          *rlornmr1prim(dd,dhpb(i),dhpb1(i),forcon(i))/dd
+C            ehpb=ehpb+fordepth(i)**4*rlornmr1(dd,dhpb(i),dhpb1(i))
+C            fac=fordepth(i)**4*rlornmr1prim(dd,dhpb(i),dhpb1(i))/dd
+C            print *,ehpb,"tu?"
+C            write(iout,*) ehpb,"btu?",
+C     & dd,dhpb(i),dhpb1(i),fordepth(i),forcon(i)
+C          write (iout,'(a6,2i5,3f8.3)') "edisl",ii,jj,
+C     &    ehpb,fordepth(i),dd
+           else   
+          if (dhpb1(i).gt.0.0d0) then
+            ehpb=ehpb+2*forcon(i)*gnmr1(dd,dhpb(i),dhpb1(i))
+            fac=forcon(i)*gnmr1prim(dd,dhpb(i),dhpb1(i))/dd
+c            write (iout,*) "alph nmr",
+c     &        dd,2*forcon(i)*gnmr1(dd,dhpb(i),dhpb1(i))
+          else
+            rdis=dd-dhpb(i)
+C Get the force constant corresponding to this distance.
+            waga=forcon(i)
+C Calculate the contribution to energy.
+            ehpb=ehpb+waga*rdis*rdis
+c            write (iout,*) "alpha reg",dd,waga*rdis*rdis
+C
+C Evaluate gradient.
+C
+            fac=waga*rdis/dd
+          endif
+          endif
+
         do j=1,3
           ggg(j)=fac*(c(j,jj)-c(j,ii))
         enddo
@@ -2964,7 +3362,7 @@ C Cartesian gradient in the SC vectors (ghpbx).
         enddo
         endif
       enddo
-      ehpb=0.5D0*ehpb
+      if (constr_dist.ne.11) ehpb=0.5D0*ehpb
       return
       end
 C--------------------------------------------------------------------------
@@ -2987,7 +3385,7 @@ C
       include 'COMMON.VAR'
       include 'COMMON.IOUNITS'
       double precision erij(3),dcosom1(3),dcosom2(3),gg(3)
-      itypi=itype(i)
+      itypi=iabs(itype(i))
       xi=c(1,nres+i)
       yi=c(2,nres+i)
       zi=c(3,nres+i)
@@ -2995,7 +3393,7 @@ C
       dyi=dc_norm(2,nres+i)
       dzi=dc_norm(3,nres+i)
       dsci_inv=dsc_inv(itypi)
-      itypj=itype(j)
+      itypj=iabs(itype(j))
       dscj_inv=dsc_inv(itypj)
       xj=c(1,nres+j)-xi
       yj=c(2,nres+j)-yi
       return
       end
 C--------------------------------------------------------------------------
+c MODELLER restraint function
+      subroutine e_modeller(ehomology_constr)
+      implicit real*8 (a-h,o-z)
+      include 'DIMENSIONS'
+      include 'DIMENSIONS.ZSCOPT'
+      include 'DIMENSIONS.FREE'
+      integer nnn, i, j, k, ki, irec, l
+      integer katy, odleglosci, test7
+      real*8 odleg, odleg2, odleg3, kat, kat2, kat3, gdih(max_template)
+      real*8 distance(max_template),distancek(max_template),
+     &    min_odl,godl(max_template),dih_diff(max_template)
+
+c
+c     FP - 30/10/2014 Temporary specifications for homology restraints
+c
+      double precision utheta_i,gutheta_i,sum_gtheta,sum_sgtheta,
+     &                 sgtheta
+      double precision, dimension (maxres) :: guscdiff,usc_diff
+      double precision, dimension (max_template) ::
+     &           gtheta,dscdiff,uscdiffk,guscdiff2,guscdiff3,
+     &           theta_diff
+
+      include 'COMMON.SBRIDGE'
+      include 'COMMON.CHAIN'
+      include 'COMMON.GEO'
+      include 'COMMON.DERIV'
+      include 'COMMON.LOCAL'
+      include 'COMMON.INTERACT'
+      include 'COMMON.VAR'
+      include 'COMMON.IOUNITS'
+      include 'COMMON.CONTROL'
+      include 'COMMON.HOMRESTR'
+c
+      include 'COMMON.SETUP'
+      include 'COMMON.NAMES'
+
+      do i=1,max_template
+        distancek(i)=9999999.9
+      enddo
+
+      odleg=0.0d0
+
+c Pseudo-energy and gradient from homology restraints (MODELLER-like
+c function)
+C AL 5/2/14 - Introduce list of restraints
+c     write(iout,*) "waga_theta",waga_theta,"waga_d",waga_d
+#ifdef DEBUG
+      write(iout,*) "------- dist restrs start -------"
+#endif
+      do ii = link_start_homo,link_end_homo
+         i = ires_homo(ii)
+         j = jres_homo(ii)
+         dij=dist(i,j)
+c        write (iout,*) "dij(",i,j,") =",dij
+         nexl=0
+         do k=1,constr_homology
+           if(.not.l_homo(k,ii)) then
+              nexl=nexl+1
+              cycle
+           endif
+           distance(k)=odl(k,ii)-dij
+c          write (iout,*) "distance(",k,") =",distance(k)
+c
+c          For Gaussian-type Urestr
+c
+           distancek(k)=0.5d0*distance(k)**2*sigma_odl(k,ii) ! waga_dist rmvd from Gaussian argument
+c          write (iout,*) "sigma_odl(",k,ii,") =",sigma_odl(k,ii)
+c          write (iout,*) "distancek(",k,") =",distancek(k)
+c          distancek(k)=0.5d0*waga_dist*distance(k)**2*sigma_odl(k,ii)
+c
+c          For Lorentzian-type Urestr
+c
+           if (waga_dist.lt.0.0d0) then
+              sigma_odlir(k,ii)=dsqrt(1/sigma_odl(k,ii))
+              distancek(k)=distance(k)**2/(sigma_odlir(k,ii)*
+     &                     (distance(k)**2+sigma_odlir(k,ii)**2))
+           endif
+         enddo
+         
+c         min_odl=minval(distancek)
+         do kk=1,constr_homology
+          if(l_homo(kk,ii)) then 
+            min_odl=distancek(kk)
+            exit
+          endif
+         enddo
+         do kk=1,constr_homology
+          if(l_homo(kk,ii) .and. distancek(kk).lt.min_odl) 
+     &              min_odl=distancek(kk)
+         enddo
+c        write (iout,* )"min_odl",min_odl
+#ifdef DEBUG
+         write (iout,*) "ij dij",i,j,dij
+         write (iout,*) "distance",(distance(k),k=1,constr_homology)
+         write (iout,*) "distancek",(distancek(k),k=1,constr_homology)
+         write (iout,* )"min_odl",min_odl
+#endif
+#ifdef OLDRESTR
+         odleg2=0.0d0
+#else
+         if (waga_dist.ge.0.0d0) then
+           odleg2=nexl
+         else
+           odleg2=0.0d0
+         endif
+#endif
+         do k=1,constr_homology
+c Nie wiem po co to liczycie jeszcze raz!
+c            odleg3=-waga_dist(iset)*((distance(i,j,k)**2)/ 
+c     &              (2*(sigma_odl(i,j,k))**2))
+           if(.not.l_homo(k,ii)) cycle
+           if (waga_dist.ge.0.0d0) then
+c
+c          For Gaussian-type Urestr
+c
+            godl(k)=dexp(-distancek(k)+min_odl)
+            odleg2=odleg2+godl(k)
+c
+c          For Lorentzian-type Urestr
+c
+           else
+            odleg2=odleg2+distancek(k)
+           endif
+
+ccc       write(iout,779) i,j,k, "odleg2=",odleg2, "odleg3=", odleg3,
+ccc     & "dEXP(odleg3)=", dEXP(odleg3),"distance(i,j,k)^2=",
+ccc     & distance(i,j,k)**2, "dist(i+1,j+1)=", dist(i+1,j+1),
+ccc     & "sigma_odl(i,j,k)=", sigma_odl(i,j,k)
+
+         enddo
+c        write (iout,*) "godl",(godl(k),k=1,constr_homology) ! exponents
+c        write (iout,*) "ii i j",ii,i,j," odleg2",odleg2 ! sum of exps
+#ifdef DEBUG
+         write (iout,*) "godl",(godl(k),k=1,constr_homology) ! exponents
+         write (iout,*) "ii i j",ii,i,j," odleg2",odleg2 ! sum of exps
+#endif
+           if (waga_dist.ge.0.0d0) then
+c
+c          For Gaussian-type Urestr
+c
+              odleg=odleg-dLOG(odleg2/constr_homology)+min_odl
+c
+c          For Lorentzian-type Urestr
+c
+           else
+              odleg=odleg+odleg2/constr_homology
+           endif
+c
+#ifdef GRAD
+c        write (iout,*) "odleg",odleg ! sum of -ln-s
+c Gradient
+c
+c          For Gaussian-type Urestr
+c
+         if (waga_dist.ge.0.0d0) sum_godl=odleg2
+         sum_sgodl=0.0d0
+         do k=1,constr_homology
+c            godl=dexp(((-(distance(i,j,k)**2)/(2*(sigma_odl(i,j,k))**2))
+c     &           *waga_dist)+min_odl
+c          sgodl=-godl(k)*distance(k)*sigma_odl(k,ii)*waga_dist
+c
+         if(.not.l_homo(k,ii)) cycle
+         if (waga_dist.ge.0.0d0) then
+c          For Gaussian-type Urestr
+c
+           sgodl=-godl(k)*distance(k)*sigma_odl(k,ii) ! waga_dist rmvd
+c
+c          For Lorentzian-type Urestr
+c
+         else
+           sgodl=-2*sigma_odlir(k,ii)*(distance(k)/(distance(k)**2+
+     &           sigma_odlir(k,ii)**2)**2)
+         endif
+           sum_sgodl=sum_sgodl+sgodl
+
+c            sgodl2=sgodl2+sgodl
+c      write(iout,*) i, j, k, distance(i,j,k), "W GRADIENCIE1"
+c      write(iout,*) "constr_homology=",constr_homology
+c      write(iout,*) i, j, k, "TEST K"
+         enddo
+         if (waga_dist.ge.0.0d0) then
+c
+c          For Gaussian-type Urestr
+c
+            grad_odl3=waga_homology(iset)*waga_dist
+     &                *sum_sgodl/(sum_godl*dij)
+c
+c          For Lorentzian-type Urestr
+c
+         else
+c Original grad expr modified by analogy w Gaussian-type Urestr grad
+c           grad_odl3=-waga_homology(iset)*waga_dist*sum_sgodl
+            grad_odl3=-waga_homology(iset)*waga_dist*
+     &                sum_sgodl/(constr_homology*dij)
+         endif
+c
+c        grad_odl3=sum_sgodl/(sum_godl*dij)
+
+
+c      write(iout,*) i, j, k, distance(i,j,k), "W GRADIENCIE2"
+c      write(iout,*) (distance(i,j,k)**2), (2*(sigma_odl(i,j,k))**2),
+c     &              (-(distance(i,j,k)**2)/(2*(sigma_odl(i,j,k))**2))
+
+ccc      write(iout,*) godl, sgodl, grad_odl3
+
+c          grad_odl=grad_odl+grad_odl3
+
+         do jik=1,3
+            ggodl=grad_odl3*(c(jik,i)-c(jik,j))
+ccc      write(iout,*) c(jik,i+1), c(jik,j+1), (c(jik,i+1)-c(jik,j+1))
+ccc      write(iout,746) "GRAD_ODL_1", i, j, jik, ggodl, 
+ccc     &              ghpbc(jik,i+1), ghpbc(jik,j+1)
+            ghpbc(jik,i)=ghpbc(jik,i)+ggodl
+            ghpbc(jik,j)=ghpbc(jik,j)-ggodl
+ccc      write(iout,746) "GRAD_ODL_2", i, j, jik, ggodl,
+ccc     &              ghpbc(jik,i+1), ghpbc(jik,j+1)
+c         if (i.eq.25.and.j.eq.27) then
+c         write(iout,*) "jik",jik,"i",i,"j",j
+c         write(iout,*) "sum_sgodl",sum_sgodl,"sgodl",sgodl
+c         write(iout,*) "grad_odl3",grad_odl3
+c         write(iout,*) "c(",jik,i,")",c(jik,i),"c(",jik,j,")",c(jik,j)
+c         write(iout,*) "ggodl",ggodl
+c         write(iout,*) "ghpbc(",jik,i,")",
+c     &                 ghpbc(jik,i),"ghpbc(",jik,j,")",
+c     &                 ghpbc(jik,j)   
+c         endif
+         enddo
+#endif
+ccc       write(iout,778)"TEST: odleg2=", odleg2, "DLOG(odleg2)=", 
+ccc     & dLOG(odleg2),"-odleg=", -odleg
+
+      enddo ! ii-loop for dist
+#ifdef DEBUG
+      write(iout,*) "------- dist restrs end -------"
+c     if (waga_angle.eq.1.0d0 .or. waga_theta.eq.1.0d0 .or. 
+c    &     waga_d.eq.1.0d0) call sum_gradient
+#endif
+c Pseudo-energy and gradient from dihedral-angle restraints from
+c homology templates
+c      write (iout,*) "End of distance loop"
+c      call flush(iout)
+      kat=0.0d0
+c      write (iout,*) idihconstr_start_homo,idihconstr_end_homo
+#ifdef DEBUG
+      write(iout,*) "------- dih restrs start -------"
+      do i=idihconstr_start_homo,idihconstr_end_homo
+        write (iout,*) "gloc_init(",i,icg,")",gloc(i,icg)
+      enddo
+#endif
+      do i=idihconstr_start_homo,idihconstr_end_homo
+        kat2=0.0d0
+c        betai=beta(i,i+1,i+2,i+3)
+        betai = phi(i)
+c       write (iout,*) "betai =",betai
+        do k=1,constr_homology
+          dih_diff(k)=pinorm(dih(k,i)-betai)
+c         write (iout,*) "dih_diff(",k,") =",dih_diff(k)
+c          if (dih_diff(i,k).gt.3.14159) dih_diff(i,k)=
+c     &                                   -(6.28318-dih_diff(i,k))
+c          if (dih_diff(i,k).lt.-3.14159) dih_diff(i,k)=
+c     &                                   6.28318+dih_diff(i,k)
+#ifdef OLD_DIHED
+          kat3=-0.5d0*dih_diff(k)**2*sigma_dih(k,i) ! waga_angle rmvd from Gaussian argument
+#else
+          kat3=(dcos(dih_diff(k))-1)*sigma_dih(k,i)
+#endif
+c         kat3=-0.5d0*waga_angle*dih_diff(k)**2*sigma_dih(k,i)
+          gdih(k)=dexp(kat3)
+          kat2=kat2+gdih(k)
+c          write(iout,*) "kat2=", kat2, "exp(kat3)=", exp(kat3)
+c          write(*,*)""
+        enddo
+c       write (iout,*) "gdih",(gdih(k),k=1,constr_homology) ! exps
+c       write (iout,*) "i",i," betai",betai," kat2",kat2 ! sum of exps
+#ifdef DEBUG
+        write (iout,*) "i",i," betai",betai," kat2",kat2
+        write (iout,*) "gdih",(gdih(k),k=1,constr_homology)
+#endif
+        if (kat2.le.1.0d-14) cycle
+        kat=kat-dLOG(kat2/constr_homology)
+c       write (iout,*) "kat",kat ! sum of -ln-s
+
+ccc       write(iout,778)"TEST: kat2=", kat2, "DLOG(kat2)=",
+ccc     & dLOG(kat2), "-kat=", -kat
+
+#ifdef GRAD
+c ----------------------------------------------------------------------
+c Gradient
+c ----------------------------------------------------------------------
+
+        sum_gdih=kat2
+        sum_sgdih=0.0d0
+        do k=1,constr_homology
+#ifdef OLD_DIHED
+          sgdih=-gdih(k)*dih_diff(k)*sigma_dih(k,i)  ! waga_angle rmvd
+#else
+          sgdih=-gdih(k)*dsin(dih_diff(k))*sigma_dih(k,i)
+#endif
+c         sgdih=-gdih(k)*dih_diff(k)*sigma_dih(k,i)*waga_angle
+          sum_sgdih=sum_sgdih+sgdih
+        enddo
+c       grad_dih3=sum_sgdih/sum_gdih
+        grad_dih3=waga_homology(iset)*waga_angle*sum_sgdih/sum_gdih
+
+c      write(iout,*)i,k,gdih,sgdih,beta(i+1,i+2,i+3,i+4),grad_dih3
+ccc      write(iout,747) "GRAD_KAT_1", i, nphi, icg, grad_dih3,
+ccc     & gloc(nphi+i-3,icg)
+        gloc(i,icg)=gloc(i,icg)+grad_dih3
+c        if (i.eq.25) then
+c        write(iout,*) "i",i,"icg",icg,"gloc(",i,icg,")",gloc(i,icg)
+c        endif
+ccc      write(iout,747) "GRAD_KAT_2", i, nphi, icg, grad_dih3,
+ccc     & gloc(nphi+i-3,icg)
+#endif
+      enddo ! i-loop for dih
+#ifdef DEBUG
+      write(iout,*) "------- dih restrs end -------"
+#endif
+
+c Pseudo-energy and gradient for theta angle restraints from
+c homology templates
+c FP 01/15 - inserted from econstr_local_test.F, loop structure
+c adapted
+
+c
+c     For constr_homology reference structures (FP)
+c     
+c     Uconst_back_tot=0.0d0
+      Eval=0.0d0
+      Erot=0.0d0
+c     Econstr_back legacy
+#ifdef GRAD
+      do i=1,nres
+c     do i=ithet_start,ithet_end
+       dutheta(i)=0.0d0
+c     enddo
+c     do i=loc_start,loc_end
+        do j=1,3
+          duscdiff(j,i)=0.0d0
+          duscdiffx(j,i)=0.0d0
+        enddo
+      enddo
+#endif
+c
+c     do iref=1,nref
+c     write (iout,*) "ithet_start =",ithet_start,"ithet_end =",ithet_end
+c     write (iout,*) "waga_theta",waga_theta
+      if (waga_theta.gt.0.0d0) then
+#ifdef DEBUG
+      write (iout,*) "usampl",usampl
+      write(iout,*) "------- theta restrs start -------"
+c     do i=ithet_start,ithet_end
+c       write (iout,*) "gloc_init(",nphi+i,icg,")",gloc(nphi+i,icg)
+c     enddo
+#endif
+c     write (iout,*) "maxres",maxres,"nres",nres
+
+      do i=ithet_start,ithet_end
+c
+c     do i=1,nfrag_back
+c       ii = ifrag_back(2,i,iset)-ifrag_back(1,i,iset)
+c
+c Deviation of theta angles wrt constr_homology ref structures
+c
+        utheta_i=0.0d0 ! argument of Gaussian for single k
+        gutheta_i=0.0d0 ! Sum of Gaussians over constr_homology ref structures
+c       do j=ifrag_back(1,i,iset)+2,ifrag_back(2,i,iset) ! original loop
+c       over residues in a fragment
+c       write (iout,*) "theta(",i,")=",theta(i)
+        do k=1,constr_homology
+c
+c         dtheta_i=theta(j)-thetaref(j,iref)
+c         dtheta_i=thetaref(k,i)-theta(i) ! original form without indexing
+          theta_diff(k)=thetatpl(k,i)-theta(i)
+c
+          utheta_i=-0.5d0*theta_diff(k)**2*sigma_theta(k,i) ! waga_theta rmvd from Gaussian argument
+c         utheta_i=-0.5d0*waga_theta*theta_diff(k)**2*sigma_theta(k,i) ! waga_theta?
+          gtheta(k)=dexp(utheta_i) ! + min_utheta_i?
+          gutheta_i=gutheta_i+dexp(utheta_i)   ! Sum of Gaussians (pk)
+c         Gradient for single Gaussian restraint in subr Econstr_back
+c         dutheta(j-2)=dutheta(j-2)+wfrag_back(1,i,iset)*dtheta_i/(ii-1)
+c
+        enddo
+c       write (iout,*) "gtheta",(gtheta(k),k=1,constr_homology) ! exps
+c       write (iout,*) "i",i," gutheta_i",gutheta_i ! sum of exps
+
+c
+#ifdef GRAD
+c         Gradient for multiple Gaussian restraint
+        sum_gtheta=gutheta_i
+        sum_sgtheta=0.0d0
+        do k=1,constr_homology
+c        New generalized expr for multiple Gaussian from Econstr_back
+         sgtheta=-gtheta(k)*theta_diff(k)*sigma_theta(k,i) ! waga_theta rmvd
+c
+c        sgtheta=-gtheta(k)*theta_diff(k)*sigma_theta(k,i)*waga_theta ! right functional form?
+          sum_sgtheta=sum_sgtheta+sgtheta ! cum variable
+        enddo
+c
+c       Final value of gradient using same var as in Econstr_back
+        dutheta(i-2)=sum_sgtheta/sum_gtheta*waga_theta
+     &               *waga_homology(iset)
+c       dutheta(i)=sum_sgtheta/sum_gtheta
+c
+c       Uconst_back=Uconst_back+waga_theta*utheta(i) ! waga_theta added as weight
+#endif
+        Eval=Eval-dLOG(gutheta_i/constr_homology)
+c       write (iout,*) "utheta(",i,")=",utheta(i) ! -ln of sum of exps
+c       write (iout,*) "Uconst_back",Uconst_back ! sum of -ln-s
+c       Uconst_back=Uconst_back+utheta(i)
+      enddo ! (i-loop for theta)
+#ifdef DEBUG
+      write(iout,*) "------- theta restrs end -------"
+#endif
+      endif
+c
+c Deviation of local SC geometry
+c
+c Separation of two i-loops (instructed by AL - 11/3/2014)
+c
+c     write (iout,*) "loc_start =",loc_start,"loc_end =",loc_end
+c     write (iout,*) "waga_d",waga_d
+
+#ifdef DEBUG
+      write(iout,*) "------- SC restrs start -------"
+      write (iout,*) "Initial duscdiff,duscdiffx"
+      do i=loc_start,loc_end
+        write (iout,*) i,(duscdiff(jik,i),jik=1,3),
+     &                 (duscdiffx(jik,i),jik=1,3)
+      enddo
+#endif
+      do i=loc_start,loc_end
+        usc_diff_i=0.0d0 ! argument of Gaussian for single k
+        guscdiff(i)=0.0d0 ! Sum of Gaussians over constr_homology ref structures
+c       do j=ifrag_back(1,i,iset)+1,ifrag_back(2,i,iset)-1 ! Econstr_back legacy
+c       write(iout,*) "xxtab, yytab, zztab"
+c       write(iout,'(i5,3f8.2)') i,xxtab(i),yytab(i),zztab(i)
+        do k=1,constr_homology
+c
+          dxx=-xxtpl(k,i)+xxtab(i) ! Diff b/w x component of ith SC vector in model and kth ref str?
+c                                    Original sign inverted for calc of gradients (s. Econstr_back)
+          dyy=-yytpl(k,i)+yytab(i) ! ibid y
+          dzz=-zztpl(k,i)+zztab(i) ! ibid z
+c         write(iout,*) "dxx, dyy, dzz"
+c         write(iout,'(2i5,3f8.2)') k,i,dxx,dyy,dzz
+c
+          usc_diff_i=-0.5d0*(dxx**2+dyy**2+dzz**2)*sigma_d(k,i)  ! waga_d rmvd from Gaussian argument
+c         usc_diff(i)=-0.5d0*waga_d*(dxx**2+dyy**2+dzz**2)*sigma_d(k,i) ! waga_d?
+c         uscdiffk(k)=usc_diff(i)
+          guscdiff2(k)=dexp(usc_diff_i) ! without min_scdiff
+          guscdiff(i)=guscdiff(i)+dexp(usc_diff_i)   !Sum of Gaussians (pk)
+c          write (iout,'(i5,6f10.5)') j,xxtab(j),yytab(j),zztab(j),
+c     &      xxref(j),yyref(j),zzref(j)
+        enddo
+c
+c       Gradient 
+c
+c       Generalized expression for multiple Gaussian acc to that for a single 
+c       Gaussian in Econstr_back as instructed by AL (FP - 03/11/2014)
+c
+c       Original implementation
+c       sum_guscdiff=guscdiff(i)
+c
+c       sum_sguscdiff=0.0d0
+c       do k=1,constr_homology
+c          sguscdiff=-guscdiff2(k)*dscdiff(k)*sigma_d(k,i)*waga_d !waga_d? 
+c          sguscdiff=-guscdiff3(k)*dscdiff(k)*sigma_d(k,i)*waga_d ! w min_uscdiff
+c          sum_sguscdiff=sum_sguscdiff+sguscdiff
+c       enddo
+c
+c       Implementation of new expressions for gradient (Jan. 2015)
+c
+c       grad_uscdiff=sum_sguscdiff/(sum_guscdiff*dtab) !?
+#ifdef GRAD
+        do k=1,constr_homology 
+c
+c       New calculation of dxx, dyy, and dzz corrected by AL (07/11), was missing and wrong
+c       before. Now the drivatives should be correct
+c
+          dxx=-xxtpl(k,i)+xxtab(i) ! Diff b/w x component of ith SC vector in model and kth ref str?
+c                                  Original sign inverted for calc of gradients (s. Econstr_back)
+          dyy=-yytpl(k,i)+yytab(i) ! ibid y
+          dzz=-zztpl(k,i)+zztab(i) ! ibid z
+c
+c         New implementation
+c
+          sum_guscdiff=guscdiff2(k)*!(dsqrt(dxx*dxx+dyy*dyy+dzz*dzz))* -> wrong!
+     &                 sigma_d(k,i) ! for the grad wrt r' 
+c         sum_sguscdiff=sum_sguscdiff+sum_guscdiff
+c
+c
+c        New implementation
+         sum_guscdiff = waga_homology(iset)*waga_d*sum_guscdiff
+         do jik=1,3
+            duscdiff(jik,i-1)=duscdiff(jik,i-1)+
+     &      sum_guscdiff*(dXX_C1tab(jik,i)*dxx+
+     &      dYY_C1tab(jik,i)*dyy+dZZ_C1tab(jik,i)*dzz)/guscdiff(i)
+            duscdiff(jik,i)=duscdiff(jik,i)+
+     &      sum_guscdiff*(dXX_Ctab(jik,i)*dxx+
+     &      dYY_Ctab(jik,i)*dyy+dZZ_Ctab(jik,i)*dzz)/guscdiff(i)
+            duscdiffx(jik,i)=duscdiffx(jik,i)+
+     &      sum_guscdiff*(dXX_XYZtab(jik,i)*dxx+
+     &      dYY_XYZtab(jik,i)*dyy+dZZ_XYZtab(jik,i)*dzz)/guscdiff(i)
+c
+#ifdef DEBUG
+             write(iout,*) "jik",jik,"i",i
+             write(iout,*) "dxx, dyy, dzz"
+             write(iout,'(2i5,3f8.2)') k,i,dxx,dyy,dzz
+             write(iout,*) "guscdiff2(",k,")",guscdiff2(k)
+c            write(iout,*) "sum_sguscdiff",sum_sguscdiff
+cc           write(iout,*) "dXX_Ctab(",jik,i,")",dXX_Ctab(jik,i)
+c            write(iout,*) "dYY_Ctab(",jik,i,")",dYY_Ctab(jik,i)
+c            write(iout,*) "dZZ_Ctab(",jik,i,")",dZZ_Ctab(jik,i)
+c            write(iout,*) "dXX_C1tab(",jik,i,")",dXX_C1tab(jik,i)
+c            write(iout,*) "dYY_C1tab(",jik,i,")",dYY_C1tab(jik,i)
+c            write(iout,*) "dZZ_C1tab(",jik,i,")",dZZ_C1tab(jik,i)
+c            write(iout,*) "dXX_XYZtab(",jik,i,")",dXX_XYZtab(jik,i)
+c            write(iout,*) "dYY_XYZtab(",jik,i,")",dYY_XYZtab(jik,i)
+c            write(iout,*) "dZZ_XYZtab(",jik,i,")",dZZ_XYZtab(jik,i)
+c            write(iout,*) "duscdiff(",jik,i-1,")",duscdiff(jik,i-1)
+c            write(iout,*) "duscdiff(",jik,i,")",duscdiff(jik,i)
+c            write(iout,*) "duscdiffx(",jik,i,")",duscdiffx(jik,i)
+c            endif
+#endif
+         enddo
+        enddo
+#endif
+c
+c       uscdiff(i)=-dLOG(guscdiff(i)/(ii-1))      ! Weighting by (ii-1) required?
+c        usc_diff(i)=-dLOG(guscdiff(i)/constr_homology) ! + min_uscdiff ?
+c
+c        write (iout,*) i," uscdiff",uscdiff(i)
+c
+c Put together deviations from local geometry
+
+c       Uconst_back=Uconst_back+wfrag_back(1,i,iset)*utheta(i)+
+c      &            wfrag_back(3,i,iset)*uscdiff(i)
+        Erot=Erot-dLOG(guscdiff(i)/constr_homology)
+c       write (iout,*) "usc_diff(",i,")=",usc_diff(i) ! -ln of sum of exps
+c       write (iout,*) "Uconst_back",Uconst_back ! cum sum of -ln-s
+c       Uconst_back=Uconst_back+usc_diff(i)
+c
+c     Gradient of multiple Gaussian restraint (FP - 04/11/2014 - right?)
+c
+c     New implment: multiplied by sum_sguscdiff
+c
+
+      enddo ! (i-loop for dscdiff)
+
+c      endif
+
+#ifdef DEBUG
+      write(iout,*) "------- SC restrs end -------"
+        write (iout,*) "------ After SC loop in e_modeller ------"
+        do i=loc_start,loc_end
+         write (iout,*) "i",i," gradc",(gradc(j,i,icg),j=1,3)
+         write (iout,*) "i",i," gradx",(gradx(j,i,icg),j=1,3)
+        enddo
+      if (waga_theta.eq.1.0d0) then
+      write (iout,*) "in e_modeller after SC restr end: dutheta"
+      do i=ithet_start,ithet_end
+        write (iout,*) i,dutheta(i)
+      enddo
+      endif
+      if (waga_d.eq.1.0d0) then
+      write (iout,*) "e_modeller after SC loop: duscdiff/x"
+      do i=1,nres
+        write (iout,*) i,(duscdiff(j,i),j=1,3)
+        write (iout,*) i,(duscdiffx(j,i),j=1,3)
+      enddo
+      endif
+#endif
+
+c Total energy from homology restraints
+#ifdef DEBUG
+      write (iout,*) "odleg",odleg," kat",kat
+      write (iout,*) "odleg",odleg," kat",kat
+      write (iout,*) "Eval",Eval," Erot",Erot
+      write (iout,*) "waga_homology(",iset,")",waga_homology(iset)
+      write (iout,*) "waga_dist ",waga_dist,"waga_angle ",waga_angle
+      write (iout,*) "waga_theta ",waga_theta,"waga_d ",waga_d
+#endif
+c
+c Addition of energy of theta angle and SC local geom over constr_homologs ref strs
+c
+c     ehomology_constr=odleg+kat
+c
+c     For Lorentzian-type Urestr
+c
+
+      if (waga_dist.ge.0.0d0) then
+c
+c          For Gaussian-type Urestr
+c
+c        ehomology_constr=(waga_dist*odleg+waga_angle*kat+
+c     &              waga_theta*Eval+waga_d*Erot)*waga_homology(iset)
+        ehomology_constr=waga_dist*odleg+waga_angle*kat+
+     &              waga_theta*Eval+waga_d*Erot
+c     write (iout,*) "ehomology_constr=",ehomology_constr
+      else
+c
+c          For Lorentzian-type Urestr
+c  
+c        ehomology_constr=(-waga_dist*odleg+waga_angle*kat+
+c     &              waga_theta*Eval+waga_d*Erot)*waga_homology(iset)
+        ehomology_constr=-waga_dist*odleg+waga_angle*kat+
+     &              waga_theta*Eval+waga_d*Erot
+c     write (iout,*) "ehomology_constr=",ehomology_constr
+      endif
+#ifdef DEBUG
+      write (iout,*) "odleg",waga_dist,odleg," kat",waga_angle,kat,
+     & "Eval",waga_theta,eval,
+     &   "Erot",waga_d,Erot
+      write (iout,*) "ehomology_constr",ehomology_constr
+#endif
+      return
+
+  748 format(a8,f12.3,a6,f12.3,a7,f12.3)
+  747 format(a12,i4,i4,i4,f8.3,f8.3)
+  746 format(a12,i4,i4,i4,f8.3,f8.3,f8.3)
+  778 format(a7,1X,f10.3,1X,a4,1X,f10.3,1X,a5,1X,f10.3)
+  779 format(i3,1X,i3,1X,i2,1X,a7,1X,f7.3,1X,a7,1X,f7.3,1X,a13,1X,
+     &       f7.3,1X,a17,1X,f9.3,1X,a10,1X,f8.3,1X,a10,1X,f8.3)
+      end
+c-----------------------------------------------------------------------
       subroutine ebond(estr)
 c
 c Evaluate the energy of stretching of the CA-CA and CA-SC virtual bonds
@@ -3060,6 +4083,7 @@ c
       implicit real*8 (a-h,o-z)
       include 'DIMENSIONS'
       include 'DIMENSIONS.ZSCOPT'
+      include 'DIMENSIONS.FREE'
       include 'COMMON.LOCAL'
       include 'COMMON.GEO'
       include 'COMMON.INTERACT'
       logical energy_dec /.false./
       double precision u(3),ud(3)
       estr=0.0d0
-      write (iout,*) "distchainmax",distchainmax
+C      write (iout,*) "distchainmax",distchainmax
+      estr1=0.0d0
+c      write (iout,*) "distchainmax",distchainmax
       do i=nnt+1,nct
-        if (itype(i-1).eq.21 .or. itype(i).eq.21) then
-          estr1=estr1+gnmr1(vbld(i),-1.0d0,distchainmax)
-          do j=1,3
-          gradb(j,i-1)=gnmr1prim(vbld(i),-1.0d0,distchainmax)
-     &      *dc(j,i-1)/vbld(i)
-          enddo
-          if (energy_dec) write(iout,*)
-     &       "estr1",i,vbld(i),distchainmax,
-     &       gnmr1(vbld(i),-1.0d0,distchainmax)
-        else
+        if (itype(i-1).eq.ntyp1 .and. itype(i).eq.ntyp1) cycle
+C          estr1=estr1+gnmr1(vbld(i),-1.0d0,distchainmax)
+C          do j=1,3
+C          gradb(j,i-1)=gnmr1prim(vbld(i),-1.0d0,distchainmax)
+C     &      *dc(j,i-1)/vbld(i)
+C          enddo
+C          if (energy_dec) write(iout,*)
+C     &       "estr1",i,vbld(i),distchainmax,
+C     &       gnmr1(vbld(i),-1.0d0,distchainmax)
+C        else
+         if (itype(i-1).eq.ntyp1 .or. itype(i).eq.ntyp1) then
+        diff = vbld(i)-vbldpDUM
+C         write(iout,*) i,diff
+         else
           diff = vbld(i)-vbldp0
 c          write (iout,*) i,vbld(i),vbldp0,diff,AKP*diff*diff
+         endif
           estr=estr+diff*diff
           do j=1,3
             gradb(j,i-1)=AKP*diff*dc(j,i-1)/vbld(i)
           enddo
-        endif
-
+C        endif
+C        write (iout,'(a7,i5,4f7.3)')
+C     &     "estr bb",i,vbld(i),vbldp0,diff,AKP*diff*diff
       enddo
-      estr=0.5d0*AKP*estr
+      estr=0.5d0*AKP*estr+estr1
 c
 c 09/18/07 AL: multimodal bond potential based on AM1 CA-SC PMF's included
 c
       do i=nnt,nct
-        iti=itype(i)
-        if (iti.ne.10 .and. iti.ne.21) then
+        iti=iabs(itype(i))
+        if (iti.ne.10 .and. iti.ne.ntyp1) then
           nbi=nbondterm(iti)
           if (nbi.eq.1) then
             diff=vbld(i+nres)-vbldsc0(1,iti)
-c            write (iout,*) i,iti,vbld(i+nres),vbldsc0(1,iti),diff,
-c     &      AKSC(1,iti),AKSC(1,iti)*diff*diff
+C            write (iout,*) i,iti,vbld(i+nres),vbldsc0(1,iti),diff,
+C     &      AKSC(1,iti),AKSC(1,iti)*diff*diff
             estr=estr+0.5d0*AKSC(1,iti)*diff*diff
             do j=1,3
               gradbx(j,i)=AKSC(1,iti)*diff*dc(j,i+nres)/vbld(i+nres)
@@ -3176,15 +4208,35 @@ c      write (iout,*) "nres",nres
 c     write (*,'(a,i2)') 'EBEND ICG=',icg
 c      write (iout,*) ithet_start,ithet_end
       do i=ithet_start,ithet_end
-        if (itype(i-1).eq.21) cycle
+C        if (itype(i-1).eq.ntyp1) cycle
+c        if (i.le.2) cycle
+        if ((itype(i-1).eq.ntyp1).or.itype(i-2).eq.ntyp1
+     &  .or.itype(i).eq.ntyp1) cycle
 C Zero the energy function and its derivative at 0 or pi.
         call splinthet(theta(i),0.5d0*delta,ss,ssd)
         it=itype(i-1)
-        if (i.gt.3 .and. itype(i-2).ne.21) then
+        ichir1=isign(1,itype(i-2))
+        ichir2=isign(1,itype(i))
+         if (itype(i-2).eq.10) ichir1=isign(1,itype(i-1))
+         if (itype(i).eq.10) ichir2=isign(1,itype(i-1))
+         if (itype(i-1).eq.10) then
+          itype1=isign(10,itype(i-2))
+          ichir11=isign(1,itype(i-2))
+          ichir12=isign(1,itype(i-2))
+          itype2=isign(10,itype(i))
+          ichir21=isign(1,itype(i))
+          ichir22=isign(1,itype(i))
+         endif
+         if (i.eq.3) then
+          y(1)=0.0D0
+          y(2)=0.0D0
+          else
+
+        if (i.gt.3 .and. itype(max0(i-3,1)).ne.ntyp1) then
 #ifdef OSF
           phii=phi(i)
-          icrc=0
-          call proc_proc(phii,icrc)
+c          icrc=0
+c          call proc_proc(phii,icrc)
           if (icrc.eq.1) phii=150.0
 #else
           phii=phi(i)
@@ -3195,11 +4247,12 @@ C Zero the energy function and its derivative at 0 or pi.
           y(1)=0.0D0
           y(2)=0.0D0
         endif
-        if (i.lt.nres .and. itype(i).ne.21) then
+        endif
+        if (i.lt.nres .and. itype(i+1).ne.ntyp1) then
 #ifdef OSF
           phii1=phi(i+1)
-          icrc=0
-          call proc_proc(phii1,icrc)
+c          icrc=0
+c          call proc_proc(phii1,icrc)
           if (icrc.eq.1) phii1=150.0
           phii1=pinorm(phii1)
           z(1)=cos(phii1)
@@ -3217,8 +4270,12 @@ C dependent on the adjacent virtual-bond-valence angles (gamma1 & gamma2).
 C In following comments this theta will be referred to as t_c.
         thet_pred_mean=0.0d0
         do k=1,2
-          athetk=athet(k,it)
-          bthetk=bthet(k,it)
+            athetk=athet(k,it,ichir1,ichir2)
+            bthetk=bthet(k,it,ichir1,ichir2)
+          if (it.eq.10) then
+             athetk=athet(k,itype1,ichir11,ichir12)
+             bthetk=bthet(k,itype2,ichir21,ichir22)
+          endif
           thet_pred_mean=thet_pred_mean+athetk*y(k)+bthetk*z(k)
         enddo
 c        write (iout,*) "thet_pred_mean",thet_pred_mean
@@ -3226,8 +4283,16 @@ c        write (iout,*) "thet_pred_mean",thet_pred_mean
         thet_pred_mean=thet_pred_mean*ss+a0thet(it)
 c        write (iout,*) "thet_pred_mean",thet_pred_mean
 C Derivatives of the "mean" values in gamma1 and gamma2.
-        dthetg1=(-athet(1,it)*y(2)+athet(2,it)*y(1))*ss
-        dthetg2=(-bthet(1,it)*z(2)+bthet(2,it)*z(1))*ss
+        dthetg1=(-athet(1,it,ichir1,ichir2)*y(2)
+     &+athet(2,it,ichir1,ichir2)*y(1))*ss
+         dthetg2=(-bthet(1,it,ichir1,ichir2)*z(2)
+     &          +bthet(2,it,ichir1,ichir2)*z(1))*ss
+         if (it.eq.10) then
+      dthetg1=(-athet(1,itype1,ichir11,ichir12)*y(2)
+     &+athet(2,itype1,ichir11,ichir12)*y(1))*ss
+        dthetg2=(-bthet(1,itype2,ichir21,ichir22)*z(2)
+     &         +bthet(2,itype2,ichir21,ichir22)*z(1))*ss
+         endif
         if (theta(i).gt.pi-delta) then
           call theteng(pi-delta,thet_pred_mean,theta0(it),f0,fprim0,
      &         E_tc0)
@@ -3250,12 +4315,41 @@ C Derivatives of the "mean" values in gamma1 and gamma2.
      &        E_theta,E_tc)
         endif
         etheta=etheta+ethetai
+c         write (iout,'(a6,i5,0pf7.3,f7.3,i5)')
+c     &      'ebend',i,ethetai,theta(i),itype(i)
 c        write (iout,'(2i3,3f8.3,f10.5)') i,it,rad2deg*theta(i),
 c     &    rad2deg*phii,rad2deg*phii1,ethetai
         if (i.gt.3) gloc(i-3,icg)=gloc(i-3,icg)+wang*E_tc*dthetg1
         if (i.lt.nres) gloc(i-2,icg)=gloc(i-2,icg)+wang*E_tc*dthetg2
         gloc(nphi+i-2,icg)=wang*(E_theta+E_tc*dthett)
- 1215   continue
+c 1215   continue
+      enddo
+      ethetacnstr=0.0d0
+C      print *,ithetaconstr_start,ithetaconstr_end,"TU"
+      do i=1,ntheta_constr
+        itheta=itheta_constr(i)
+        thetiii=theta(itheta)
+        difi=pinorm(thetiii-theta_constr0(i))
+        if (difi.gt.theta_drange(i)) then
+          difi=difi-theta_drange(i)
+          ethetacnstr=ethetacnstr+0.25d0*for_thet_constr(i)*difi**4
+          gloc(itheta+nphi-2,icg)=gloc(itheta+nphi-2,icg)
+     &    +for_thet_constr(i)*difi**3
+        else if (difi.lt.-drange(i)) then
+          difi=difi+drange(i)
+          ethetacnstr=ethetacnstr+0.25d0*for_thet_constr(i)*difi**4
+          gloc(itheta+nphi-2,icg)=gloc(itheta+nphi-2,icg)
+     &    +for_thet_constr(i)*difi**3
+        else
+          difi=0.0
+        endif
+C       if (energy_dec) then
+C        write (iout,'(a6,2i5,4f8.3,2e14.5)') "ethetc",
+C     &    i,itheta,rad2deg*thetiii,
+C     &    rad2deg*theta_constr0(i),  rad2deg*theta_drange(i),
+C     &    rad2deg*difi,0.25d0*for_thet_constr(i)*difi**4,
+C     &    gloc(itheta+nphi-2,icg)
+C        endif
       enddo
 C Ufff.... We've done all this!!! 
       return
@@ -3380,6 +4474,7 @@ C
       implicit real*8 (a-h,o-z)
       include 'DIMENSIONS'
       include 'DIMENSIONS.ZSCOPT'
+      include 'DIMENSIONS.FREE'
       include 'COMMON.LOCAL'
       include 'COMMON.GEO'
       include 'COMMON.INTERACT'
@@ -3390,6 +4485,7 @@ C
       include 'COMMON.NAMES'
       include 'COMMON.FFIELD'
       include 'COMMON.CONTROL'
+      include 'COMMON.TORCNSTR'
       double precision coskt(mmaxtheterm),sinkt(mmaxtheterm),
      & cosph1(maxsingle),sinph1(maxsingle),cosph2(maxsingle),
      & sinph2(maxsingle),cosph1ph2(maxdouble,maxdouble),
       etheta=0.0D0
 c      write (iout,*) "ithetyp",(ithetyp(i),i=1,ntyp1)
       do i=ithet_start,ithet_end
-        if (itype(i-1).eq.21) cycle
+c        if (i.eq.2) cycle
+c        print *,i,itype(i-1),itype(i),itype(i-2)
+        if ((itype(i-1).eq.ntyp1).or.(itype(i-2).eq.ntyp1)
+     &  .or.(itype(i).eq.ntyp1)) cycle
+C In current verion the ALL DUMMY ATOM POTENTIALS ARE OFF
+
+        if (iabs(itype(i+1)).eq.20) iblock=2
+        if (iabs(itype(i+1)).ne.20) iblock=1
         dethetai=0.0d0
         dephii=0.0d0
         dephii1=0.0d0
         theti2=0.5d0*theta(i)
-        ityp2=ithetyp(itype(i-1))
+        ityp2=ithetyp((itype(i-1)))
         do k=1,nntheterm
           coskt(k)=dcos(k*theti2)
           sinkt(k)=dsin(k*theti2)
         enddo
-        if (i.gt.3 .and. itype(i-2).ne.21) then
+        if (i.gt.3 .and. itype(max0(i-3,1)).ne.ntyp1) then
 #ifdef OSF
           phii=phi(i)
           if (phii.ne.phii) phii=150.0
 #else
           phii=phi(i)
 #endif
-          ityp1=ithetyp(itype(i-2))
+          ityp1=ithetyp((itype(i-2)))
           do k=1,nsingle
             cosph1(k)=dcos(k*phii)
             sinph1(k)=dsin(k*phii)
           enddo
         else
           phii=0.0d0
-          ityp1=nthetyp+1
+          ityp1=ithetyp(itype(i-2))
           do k=1,nsingle
             cosph1(k)=0.0d0
             sinph1(k)=0.0d0
           enddo 
         endif
-        if (i.lt.nres .and. itype(i).ne.21) then
+        if (i.lt.nres .and. itype(i+1).ne.ntyp1) then
 #ifdef OSF
           phii1=phi(i+1)
           if (phii1.ne.phii1) phii1=150.0
@@ -3436,14 +4539,14 @@ c      write (iout,*) "ithetyp",(ithetyp(i),i=1,ntyp1)
 #else
           phii1=phi(i+1)
 #endif
-          ityp3=ithetyp(itype(i))
+          ityp3=ithetyp((itype(i)))
           do k=1,nsingle
             cosph2(k)=dcos(k*phii1)
             sinph2(k)=dsin(k*phii1)
           enddo
         else
           phii1=0.0d0
-          ityp3=nthetyp+1
+          ityp3=ithetyp(itype(i))
           do k=1,nsingle
             cosph2(k)=0.0d0
             sinph2(k)=0.0d0
@@ -3452,7 +4555,7 @@ c      write (iout,*) "ithetyp",(ithetyp(i),i=1,ntyp1)
 c        write (iout,*) "i",i," ityp1",itype(i-2),ityp1,
 c     &   " ityp2",itype(i-1),ityp2," ityp3",itype(i),ityp3
 c        call flush(iout)
-        ethetai=aa0thet(ityp1,ityp2,ityp3)
+        ethetai=aa0thet(ityp1,ityp2,ityp3,iblock)
         do k=1,ndouble
           do l=1,k-1
             ccl=cosph1(l)*cosph2(k-l)
@@ -3474,11 +4577,12 @@ c        call flush(iout)
         enddo
         endif
         do k=1,ntheterm
-          ethetai=ethetai+aathet(k,ityp1,ityp2,ityp3)*sinkt(k)
-          dethetai=dethetai+0.5d0*k*aathet(k,ityp1,ityp2,ityp3)
+          ethetai=ethetai+aathet(k,ityp1,ityp2,ityp3,iblock)*sinkt(k)
+          dethetai=dethetai+0.5d0*k*aathet(k,ityp1,ityp2,ityp3,iblock)
      &      *coskt(k)
           if (lprn)
-     &    write (iout,*) "k",k," aathet",aathet(k,ityp1,ityp2,ityp3),
+     &    write (iout,*) "k",k,"
+     &      aathet",aathet(k,ityp1,ityp2,ityp3,iblock),
      &     " ethetai",ethetai
         enddo
         if (lprn) then
@@ -3497,24 +4601,24 @@ c        call flush(iout)
         endif
         do m=1,ntheterm2
           do k=1,nsingle
-            aux=bbthet(k,m,ityp1,ityp2,ityp3)*cosph1(k)
-     &         +ccthet(k,m,ityp1,ityp2,ityp3)*sinph1(k)
-     &         +ddthet(k,m,ityp1,ityp2,ityp3)*cosph2(k)
-     &         +eethet(k,m,ityp1,ityp2,ityp3)*sinph2(k)
+            aux=bbthet(k,m,ityp1,ityp2,ityp3,iblock)*cosph1(k)
+     &         +ccthet(k,m,ityp1,ityp2,ityp3,iblock)*sinph1(k)
+     &         +ddthet(k,m,ityp1,ityp2,ityp3,iblock)*cosph2(k)
+     &         +eethet(k,m,ityp1,ityp2,ityp3,iblock)*sinph2(k)
             ethetai=ethetai+sinkt(m)*aux
             dethetai=dethetai+0.5d0*m*aux*coskt(m)
             dephii=dephii+k*sinkt(m)*(
-     &          ccthet(k,m,ityp1,ityp2,ityp3)*cosph1(k)-
-     &          bbthet(k,m,ityp1,ityp2,ityp3)*sinph1(k))
+     &          ccthet(k,m,ityp1,ityp2,ityp3,iblock)*cosph1(k)-
+     &          bbthet(k,m,ityp1,ityp2,ityp3,iblock)*sinph1(k))
             dephii1=dephii1+k*sinkt(m)*(
-     &          eethet(k,m,ityp1,ityp2,ityp3)*cosph2(k)-
-     &          ddthet(k,m,ityp1,ityp2,ityp3)*sinph2(k))
+     &          eethet(k,m,ityp1,ityp2,ityp3,iblock)*cosph2(k)-
+     &          ddthet(k,m,ityp1,ityp2,ityp3,iblock)*sinph2(k))
             if (lprn)
      &      write (iout,*) "m",m," k",k," bbthet",
-     &         bbthet(k,m,ityp1,ityp2,ityp3)," ccthet",
-     &         ccthet(k,m,ityp1,ityp2,ityp3)," ddthet",
-     &         ddthet(k,m,ityp1,ityp2,ityp3)," eethet",
-     &         eethet(k,m,ityp1,ityp2,ityp3)," ethetai",ethetai
+     &         bbthet(k,m,ityp1,ityp2,ityp3,iblock)," ccthet",
+     &         ccthet(k,m,ityp1,ityp2,ityp3,iblock)," ddthet",
+     &         ddthet(k,m,ityp1,ityp2,ityp3,iblock)," eethet",
+     &         eethet(k,m,ityp1,ityp2,ityp3,iblock)," ethetai",ethetai
           enddo
         enddo
         if (lprn)
@@ -3522,28 +4626,29 @@ c        call flush(iout)
         do m=1,ntheterm3
           do k=2,ndouble
             do l=1,k-1
-              aux=ffthet(l,k,m,ityp1,ityp2,ityp3)*cosph1ph2(l,k)+
-     &            ffthet(k,l,m,ityp1,ityp2,ityp3)*cosph1ph2(k,l)+
-     &            ggthet(l,k,m,ityp1,ityp2,ityp3)*sinph1ph2(l,k)+
-     &            ggthet(k,l,m,ityp1,ityp2,ityp3)*sinph1ph2(k,l)
+              aux=ffthet(l,k,m,ityp1,ityp2,ityp3,iblock)*cosph1ph2(l,k)+
+     &            ffthet(k,l,m,ityp1,ityp2,ityp3,iblock)*cosph1ph2(k,l)+
+     &            ggthet(l,k,m,ityp1,ityp2,ityp3,iblock)*sinph1ph2(l,k)+
+     &            ggthet(k,l,m,ityp1,ityp2,ityp3,iblock)*sinph1ph2(k,l)
               ethetai=ethetai+sinkt(m)*aux
               dethetai=dethetai+0.5d0*m*coskt(m)*aux
               dephii=dephii+l*sinkt(m)*(
-     &           -ffthet(l,k,m,ityp1,ityp2,ityp3)*sinph1ph2(l,k)-
-     &            ffthet(k,l,m,ityp1,ityp2,ityp3)*sinph1ph2(k,l)+
-     &            ggthet(l,k,m,ityp1,ityp2,ityp3)*cosph1ph2(l,k)+
-     &            ggthet(k,l,m,ityp1,ityp2,ityp3)*cosph1ph2(k,l))
+     &           -ffthet(l,k,m,ityp1,ityp2,ityp3,iblock)*sinph1ph2(l,k)-
+     &            ffthet(k,l,m,ityp1,ityp2,ityp3,iblock)*sinph1ph2(k,l)+
+     &            ggthet(l,k,m,ityp1,ityp2,ityp3,iblock)*cosph1ph2(l,k)+
+     &            ggthet(k,l,m,ityp1,ityp2,ityp3,iblock)*cosph1ph2(k,l))
               dephii1=dephii1+(k-l)*sinkt(m)*(
-     &           -ffthet(l,k,m,ityp1,ityp2,ityp3)*sinph1ph2(l,k)+
-     &            ffthet(k,l,m,ityp1,ityp2,ityp3)*sinph1ph2(k,l)+
-     &            ggthet(l,k,m,ityp1,ityp2,ityp3)*cosph1ph2(l,k)-
-     &            ggthet(k,l,m,ityp1,ityp2,ityp3)*cosph1ph2(k,l))
+     &           -ffthet(l,k,m,ityp1,ityp2,ityp3,iblock)*sinph1ph2(l,k)+
+     &            ffthet(k,l,m,ityp1,ityp2,ityp3,iblock)*sinph1ph2(k,l)+
+     &            ggthet(l,k,m,ityp1,ityp2,ityp3,iblock)*cosph1ph2(l,k)-
+     &            ggthet(k,l,m,ityp1,ityp2,ityp3,iblock)*cosph1ph2(k,l))
               if (lprn) then
               write (iout,*) "m",m," k",k," l",l," ffthet",
-     &            ffthet(l,k,m,ityp1,ityp2,ityp3),
-     &            ffthet(k,l,m,ityp1,ityp2,ityp3)," ggthet",
-     &            ggthet(l,k,m,ityp1,ityp2,ityp3),
-     &            ggthet(k,l,m,ityp1,ityp2,ityp3)," ethetai",ethetai
+     &            ffthet(l,k,m,ityp1,ityp2,ityp3,iblock),
+     &            ffthet(k,l,m,ityp1,ityp2,ityp3,iblock)," ggthet",
+     &            ggthet(l,k,m,ityp1,ityp2,ityp3,iblock),
+     &            ggthet(k,l,m,ityp1,ityp2,ityp3,iblock),
+     &            " ethetai",ethetai
               write (iout,*) cosph1ph2(l,k)*sinkt(m),
      &            cosph1ph2(k,l)*sinkt(m),
      &            sinph1ph2(l,k)*sinkt(m),sinph1ph2(k,l)*sinkt(m)
@@ -3558,10 +4663,40 @@ c        call flush(iout)
         etheta=etheta+ethetai
         if (i.gt.3) gloc(i-3,icg)=gloc(i-3,icg)+wang*dephii
         if (i.lt.nres) gloc(i-2,icg)=gloc(i-2,icg)+wang*dephii1
-        gloc(nphi+i-2,icg)=wang*dethetai
+c        gloc(nphi+i-2,icg)=wang*dethetai
+        gloc(nphi+i-2,icg)=gloc(nphi+i-2,icg)+wang*dethetai
+      enddo
+C now constrains
+      ethetacnstr=0.0d0
+C      print *,ithetaconstr_start,ithetaconstr_end,"TU"
+      do i=1,ntheta_constr
+        itheta=itheta_constr(i)
+        thetiii=theta(itheta)
+        difi=pinorm(thetiii-theta_constr0(i))
+        if (difi.gt.theta_drange(i)) then
+          difi=difi-theta_drange(i)
+          ethetacnstr=ethetacnstr+0.25d0*for_thet_constr(i)*difi**4
+          gloc(itheta+nphi-2,icg)=gloc(itheta+nphi-2,icg)
+     &    +for_thet_constr(i)*difi**3
+        else if (difi.lt.-drange(i)) then
+          difi=difi+drange(i)
+          ethetacnstr=ethetacnstr+0.25d0*for_thet_constr(i)*difi**4
+          gloc(itheta+nphi-2,icg)=gloc(itheta+nphi-2,icg)
+     &    +for_thet_constr(i)*difi**3
+        else
+          difi=0.0
+        endif
+C       if (energy_dec) then
+C        write (iout,'(a6,2i5,4f8.3,2e14.5)') "ethetc",
+C     &    i,itheta,rad2deg*thetiii,
+C     &    rad2deg*theta_constr0(i),  rad2deg*theta_drange(i),
+C     &    rad2deg*difi,0.25d0*for_thet_constr(i)*difi**4,
+C     &    gloc(itheta+nphi-2,icg)
+C        endif
       enddo
       return
       end
+
 #endif
 #ifdef CRYST_SC
 c-----------------------------------------------------------------------------
@@ -3586,14 +4721,14 @@ C ALPHA and OMEGA.
       common /sccalc/ time11,time12,time112,theti,it,nlobit
       delta=0.02d0*pi
       escloc=0.0D0
-c     write (iout,'(a)') 'ESC'
+C      write (iout,*) 'ESC'
       do i=loc_start,loc_end
         it=itype(i)
-        if (it.eq.21) cycle
+        if (it.eq.ntyp1) cycle
         if (it.eq.10) goto 1
-        nlobit=nlob(it)
+        nlobit=nlob(iabs(it))
 c       print *,'i=',i,' it=',it,' nlobit=',nlobit
-c       write (iout,*) 'i=',i,' ssa=',ssa,' ssad=',ssad
+C        write (iout,*) 'i=',i,' ssa=',ssa,' ssad=',ssad
         theti=theta(i+1)-pipol
         x(1)=dtan(theti)
         x(2)=alph(i)
@@ -3629,8 +4764,8 @@ c        write (iout,*) "i",i," x",x(1),x(2),x(3)
             dersc(k)=ss*dersc(k)+(1.0d0-ss)*dersc0(k)
           enddo
           dersc(2)=dersc(2)+ssd*(escloci-esclocbi)
-c         write (iout,*) 'i=',i,x(2)*rad2deg,escloci0,escloci,
-c    &             esclocbi,ss,ssd
+          write (iout,*) 'i=',i,x(2)*rad2deg,escloci0,escloci,
+     &             esclocbi,ss,ssd
           escloci=ss*escloci+(1.0d0-ss)*esclocbi
 c         escloci=esclocbi
 c         write (iout,*) escloci
@@ -3664,15 +4799,17 @@ c         write (iout,*) escloci
           enddo
           dersc(2)=dersc(2)+ssd*(escloci-esclocbi)
 c         write (iout,*) 'i=',i,x(2)*rad2deg,escloci0,escloci,
-c    &             esclocbi,ss,ssd
+c     &             esclocbi,ss,ssd
           escloci=ss*escloci+(1.0d0-ss)*esclocbi
-c         write (iout,*) escloci
+C         write (iout,*) 'i=',i, escloci
         else
           call enesc(x,escloci,dersc,ddummy,.false.)
         endif
 
         escloc=escloc+escloci
-c        write (iout,*) 'i=',i,' escloci=',escloci,' dersc=',dersc
+C        write (iout,*) 'i=',i,' escloci=',escloci,' dersc=',dersc
+            write (iout,'(a6,i5,0pf7.3)')
+     &     'escloc',i,escloci
 
         gloc(nphi+i-1,icg)=gloc(nphi+i-1,icg)+
      &   wscloc*dersc(1)
@@ -3746,7 +4883,7 @@ C Compute the contribution to SC energy and derivatives
         do iii=-1,1
 
           do j=1,nlobit
-            expfac=dexp(bsc(j,it)-0.5D0*contr(j,iii)+emin)
+            expfac=dexp(bsc(j,iabs(it))-0.5D0*contr(j,iii)+emin)
 cd          print *,'j=',j,' expfac=',expfac
             escloc_i=escloc_i+expfac
             do k=1,3
@@ -3827,7 +4964,7 @@ C Compute the contribution to SC energy and derivatives
 
       dersc12=0.0d0
       do j=1,nlobit
-        expfac=dexp(bsc(j,it)-0.5D0*contr(j)+emin)
+        expfac=dexp(bsc(j,iabs(it))-0.5D0*contr(j)+emin)
         escloc_i=escloc_i+expfac
         do k=1,2
           dersc(k)=dersc(k)+Ax(k,j)*expfac
@@ -3857,6 +4994,7 @@ C
       implicit real*8 (a-h,o-z)
       include 'DIMENSIONS'
       include 'DIMENSIONS.ZSCOPT'
+      include 'DIMENSIONS.FREE'
       include 'COMMON.GEO'
       include 'COMMON.LOCAL'
       include 'COMMON.VAR'
@@ -3882,7 +5020,7 @@ C
       delta=0.02d0*pi
       escloc=0.0D0
       do i=loc_start,loc_end
-        if (itype(i).eq.21) cycle
+        if (itype(i).eq.ntyp1) cycle
         costtab(i+1) =dcos(theta(i+1))
         sinttab(i+1) =dsqrt(1-costtab(i+1)*costtab(i+1))
         cost2tab(i+1)=dsqrt(0.5d0*(1.0d0+costtab(i+1)))
@@ -3891,7 +5029,7 @@ C
         cosfac=dsqrt(cosfac2)
         sinfac2=0.5d0/(1.0d0-costtab(i+1))
         sinfac=dsqrt(sinfac2)
-        it=itype(i)
+        it=iabs(itype(i))
         if (it.eq.10) goto 1
 c
 C  Compute the axes of tghe local cartesian coordinates system; store in
@@ -3909,7 +5047,7 @@ C     &   dc_norm(3,i+nres)
           y_prime(j) = (dc_norm(j,i) + dc_norm(j,i-1))*sinfac
         enddo
         do j = 1,3
-          z_prime(j) = -uz(j,i-1)
+          z_prime(j) = -uz(j,i-1)*dsign(1.0d0,dfloat(itype(i)))
         enddo     
 c       write (2,*) "i",i
 c       write (2,*) "x_prime",(x_prime(j),j=1,3)
@@ -3941,7 +5079,7 @@ C
 C Compute the energy of the ith side cbain
 C
 c        write (2,*) "xx",xx," yy",yy," zz",zz
-        it=itype(i)
+        it=iabs(itype(i))
         do j = 1,65
           x(j) = sc_parmin(j,it) 
         enddo
@@ -3949,7 +5087,7 @@ c        write (2,*) "xx",xx," yy",yy," zz",zz
 Cc diagnostics - remove later
         xx1 = dcos(alph(2))
         yy1 = dsin(alph(2))*dcos(omeg(2))
-        zz1 = -dsin(alph(2))*dsin(omeg(2))
+        zz1 = -dsign(1.0d0,itype(i))*dsin(alph(2))*dsin(omeg(2))
         write(2,'(3f8.1,3f9.3,1x,3f9.3)') 
      &    alph(2)*rad2deg,omeg(2)*rad2deg,theta(3)*rad2deg,xx,yy,zz,
      &    xx1,yy1,zz1
@@ -3992,6 +5130,8 @@ c     &   dscp1,dscp2,sumene
 c        sumene = enesc(x,xx,yy,zz,cost2tab(i+1),sint2tab(i+1))
         escloc = escloc + sumene
 c        write (2,*) "escloc",escloc
+c        write (2,*) "i",i," escloc",sumene,escloc,it,itype(i),
+c     &  zz,xx,yy
         if (.not. calc_grad) goto 1
 #ifdef DEBUG
 C
@@ -4120,8 +5260,10 @@ c     &   (dC_norm(j,i-1),j=1,3)," vbld_inv",vbld_inv(i+1),vbld_inv(i)
          dZZ_Ci1(k)=0.0d0
          dZZ_Ci(k)=0.0d0
          do j=1,3
-           dZZ_Ci(k)=dZZ_Ci(k)-uzgrad(j,k,2,i-1)*dC_norm(j,i+nres)
-           dZZ_Ci1(k)=dZZ_Ci1(k)-uzgrad(j,k,1,i-1)*dC_norm(j,i+nres)
+           dZZ_Ci(k)=dZZ_Ci(k)-uzgrad(j,k,2,i-1)
+     & *dsign(1.0d0,dfloat(itype(i)))*dC_norm(j,i+nres)
+           dZZ_Ci1(k)=dZZ_Ci1(k)-uzgrad(j,k,1,i-1)
+     &  *dsign(1.0d0,dfloat(itype(i)))*dC_norm(j,i+nres)
          enddo
           
          dXX_XYZ(k)=vbld_inv(i+nres)*(x_prime(k)-xx*dC_norm(k,i+nres))
@@ -4273,8 +5415,8 @@ C Set lprn=.true. for debugging
 c      lprn=.true.
       etors=0.0D0
       do i=iphi_start,iphi_end
-        if (itype(i-2).eq.21 .or. itype(i-1).eq.21
-     &      .or. itype(i).eq.21) cycle
+        if (itype(i-2).eq.ntyp1 .or. itype(i-1).eq.ntyp1
+     &      .or. itype(i).eq.ntyp1) cycle
        itori=itortyp(itype(i-2))
        itori1=itortyp(itype(i-1))
         phii=phi(i)
@@ -4322,15 +5464,16 @@ c       write (iout,*) 'i=',i,' gloc=',gloc(i-3,icg)
         difi=phii-phi0(i)
         if (difi.gt.drange(i)) then
           difi=difi-drange(i)
-          edihcnstr=edihcnstr+0.25d0*ftors*difi**4
-          gloc(itori-3,icg)=gloc(itori-3,icg)+ftors*difi**3
+          edihcnstr=edihcnstr+0.25d0*ftors(i)*difi**4
+          gloc(itori-3,icg)=gloc(itori-3,icg)+ftors(i)*difi**3
         else if (difi.lt.-drange(i)) then
           difi=difi+drange(i)
-          edihcnstr=edihcnstr+0.25d0*ftors*difi**4
-          gloc(itori-3,icg)=gloc(itori-3,icg)+ftors*difi**3
+          edihcnstr=edihcnstr+0.25d0*ftors(i)*difi**4
+          gloc(itori-3,icg)=gloc(itori-3,icg)+ftors(i)*difi**3
         endif
-!        write (iout,'(2i5,2f8.3,2e14.5)') i,itori,rad2deg*phii,
-!     &    rad2deg*difi,0.25d0*ftors*difi**4,gloc(itori-3,icg)
+C        write (iout,'(a6,2i5,2f8.3,2e14.5)') "edih",
+C     &    i,itori,rad2deg*phii,
+C     &    rad2deg*difi,0.25d0*ftors(i)*difi**4,gloc(itori-3,icg)
       enddo
 !      write (iout,*) 'edihcnstr',edihcnstr
       return
@@ -4358,17 +5501,25 @@ C Set lprn=.true. for debugging
 c      lprn=.true.
       etors=0.0D0
       do i=iphi_start,iphi_end
-        if (itype(i-2).eq.21 .or. itype(i-1).eq.21
-     &       .or. itype(i).eq.21) cycle
+        if (i.le.2) cycle
+        if (itype(i-2).eq.ntyp1.or. itype(i-1).eq.ntyp1
+     &      .or. itype(i).eq.ntyp1 .or. itype(i-3).eq.ntyp1) cycle
+C        if (itype(i-2).eq.ntyp1 .or. itype(i-1).eq.ntyp1
+C     &       .or. itype(i).eq.ntyp1) cycle
         if (itel(i-2).eq.0 .or. itel(i-1).eq.0) goto 1215
+         if (iabs(itype(i)).eq.20) then
+         iblock=2
+         else
+         iblock=1
+         endif
         itori=itortyp(itype(i-2))
         itori1=itortyp(itype(i-1))
         phii=phi(i)
         gloci=0.0D0
 C Regular cosine and sine terms
-        do j=1,nterm(itori,itori1)
-          v1ij=v1(j,itori,itori1)
-          v2ij=v2(j,itori,itori1)
+        do j=1,nterm(itori,itori1,iblock)
+          v1ij=v1(j,itori,itori1,iblock)
+          v2ij=v2(j,itori,itori1,iblock)
           cosphi=dcos(j*phii)
           sinphi=dsin(j*phii)
           etors=etors+v1ij*cosphi+v2ij*sinphi
@@ -4381,22 +5532,24 @@ C          [v2 cos(phi/2)+v3 sin(phi/2)]^2 + 1
 C
         cosphi=dcos(0.5d0*phii)
         sinphi=dsin(0.5d0*phii)
-        do j=1,nlor(itori,itori1)
+        do j=1,nlor(itori,itori1,iblock)
           vl1ij=vlor1(j,itori,itori1)
           vl2ij=vlor2(j,itori,itori1)
           vl3ij=vlor3(j,itori,itori1)
           pom=vl2ij*cosphi+vl3ij*sinphi
           pom1=1.0d0/(pom*pom+1.0d0)
           etors=etors+vl1ij*pom1
+c          if (energy_dec) etors_ii=etors_ii+
+c     &                vl1ij*pom1
           pom=-pom*pom1*pom1
           gloci=gloci+vl1ij*(vl3ij*cosphi-vl2ij*sinphi)*pom
         enddo
 C Subtract the constant term
-        etors=etors-v0(itori,itori1)
+        etors=etors-v0(itori,itori1,iblock)
         if (lprn)
      &  write (iout,'(2(a3,2x,i3,2x),2i3,6f8.3/26x,6f8.3/)')
      &  restyp(itype(i-2)),i-2,restyp(itype(i-1)),i-1,itori,itori1,
-     &  (v1(j,itori,itori1),j=1,6),(v2(j,itori,itori1),j=1,6)
+     &  (v1(j,itori,itori1,1),j=1,6),(v2(j,itori,itori1,1),j=1,6)
         gloc(i-3,icg)=gloc(i-3,icg)+wtor*fact*gloci
 c       write (iout,*) 'i=',i,' gloc=',gloc(i-3,icg)
  1215   continue
@@ -4410,21 +5563,24 @@ c       write (iout,*) 'i=',i,' gloc=',gloc(i-3,icg)
         edihi=0.0d0
         if (difi.gt.drange(i)) then
           difi=difi-drange(i)
-          edihcnstr=edihcnstr+0.25d0*ftors*difi**4
-          gloc(itori-3,icg)=gloc(itori-3,icg)+ftors*difi**3
-          edihi=0.25d0*ftors*difi**4
+          edihcnstr=edihcnstr+0.25d0*ftors(i)*difi**4
+          gloc(itori-3,icg)=gloc(itori-3,icg)+ftors(i)*difi**3
+          edihi=0.25d0*ftors(i)*difi**4
         else if (difi.lt.-drange(i)) then
           difi=difi+drange(i)
-          edihcnstr=edihcnstr+0.25d0*ftors*difi**4
-          gloc(itori-3,icg)=gloc(itori-3,icg)+ftors*difi**3
-          edihi=0.25d0*ftors*difi**4
+          edihcnstr=edihcnstr+0.25d0*ftors(i)*difi**4
+          gloc(itori-3,icg)=gloc(itori-3,icg)+ftors(i)*difi**3
+          edihi=0.25d0*ftors(i)*difi**4
         else
           difi=0.0d0
         endif
+        write (iout,'(a6,2i5,2f8.3,2e14.5)') "edih",
+     &    i,itori,rad2deg*phii,
+     &    rad2deg*difi,0.25d0*ftors(i)*difi**4
 c        write (iout,'(2i5,4f10.5,e15.5)') i,itori,phii,phi0(i),difi,
 c     &    drange(i),edihi
 !        write (iout,'(2i5,2f8.3,2e14.5)') i,itori,rad2deg*phii,
-!     &    rad2deg*difi,0.25d0*ftors*difi**4,gloc(itori-3,icg)
+!     &    rad2deg*difi,0.25d0*ftors(i)*difi**4,gloc(itori-3,icg)
       enddo
 !      write (iout,*) 'edihcnstr',edihcnstr
       return
@@ -4452,8 +5608,12 @@ C Set lprn=.true. for debugging
 c     lprn=.true.
       etors_d=0.0D0
       do i=iphi_start,iphi_end-1
-        if (itype(i-2).eq.21 .or. itype(i-1).eq.21
-     &      .or. itype(i).eq.21 .or. itype(i+1).eq.21) cycle
+        if (i.le.3) cycle
+C        if (itype(i-2).eq.ntyp1.or. itype(i-1).eq.ntyp1
+C     &      .or. itype(i).eq.ntyp1 .or. itype(i+1).eq.ntyp1) cycle
+         if ((itype(i-2).eq.ntyp1).or.itype(i-3).eq.ntyp1.or.
+     &  (itype(i-1).eq.ntyp1).or.(itype(i).eq.ntyp1).or.
+     &  (itype(i+1).eq.ntyp1)) cycle
         if (itel(i-2).eq.0 .or. itel(i-1).eq.0 .or. itel(i).eq.0) 
      &     goto 1215
         itori=itortyp(itype(i-2))
@@ -4463,12 +5623,14 @@ c     lprn=.true.
         phii1=phi(i+1)
         gloci1=0.0D0
         gloci2=0.0D0
+        iblock=1
+        if (iabs(itype(i+1)).eq.20) iblock=2
 C Regular cosine and sine terms
-        do j=1,ntermd_1(itori,itori1,itori2)
-          v1cij=v1c(1,j,itori,itori1,itori2)
-          v1sij=v1s(1,j,itori,itori1,itori2)
-          v2cij=v1c(2,j,itori,itori1,itori2)
-          v2sij=v1s(2,j,itori,itori1,itori2)
+        do j=1,ntermd_1(itori,itori1,itori2,iblock)
+          v1cij=v1c(1,j,itori,itori1,itori2,iblock)
+          v1sij=v1s(1,j,itori,itori1,itori2,iblock)
+          v2cij=v1c(2,j,itori,itori1,itori2,iblock)
+          v2sij=v1s(2,j,itori,itori1,itori2,iblock)
           cosphi1=dcos(j*phii)
           sinphi1=dsin(j*phii)
           cosphi2=dcos(j*phii1)
@@ -4478,12 +5640,12 @@ C Regular cosine and sine terms
           gloci1=gloci1+j*(v1sij*cosphi1-v1cij*sinphi1)
           gloci2=gloci2+j*(v2sij*cosphi2-v2cij*sinphi2)
         enddo
-        do k=2,ntermd_2(itori,itori1,itori2)
+        do k=2,ntermd_2(itori,itori1,itori2,iblock)
           do l=1,k-1
-            v1cdij = v2c(k,l,itori,itori1,itori2)
-            v2cdij = v2c(l,k,itori,itori1,itori2)
-            v1sdij = v2s(k,l,itori,itori1,itori2)
-            v2sdij = v2s(l,k,itori,itori1,itori2)
+            v1cdij = v2c(k,l,itori,itori1,itori2,iblock)
+            v2cdij = v2c(l,k,itori,itori1,itori2,iblock)
+            v1sdij = v2s(k,l,itori,itori1,itori2,iblock)
+            v2sdij = v2s(l,k,itori,itori1,itori2,iblock)
             cosphi1p2=dcos(l*phii+(k-l)*phii1)
             cosphi1m2=dcos(l*phii-(k-l)*phii1)
             sinphi1p2=dsin(l*phii+(k-l)*phii1)
@@ -4493,7 +5655,7 @@ C Regular cosine and sine terms
             gloci1=gloci1+l*(v1sdij*cosphi1p2+v2sdij*cosphi1m2
      &        -v1cdij*sinphi1p2-v2cdij*sinphi1m2)
             gloci2=gloci2+(k-l)*(v1sdij*cosphi1p2-v2sdij*cosphi1m2
-     &        -v1cdij*sinphi1p2+v2cdij*sinphi1m2) 
+     &        -v1cdij*sinphi1p2+v2cdij*sinphi1m2)
           enddo
         enddo
         gloc(i-3,icg)=gloc(i-3,icg)+wtor_d*fact2*gloci1
@@ -4514,6 +5676,7 @@ c        amino-acid residues.
       implicit real*8 (a-h,o-z)
       include 'DIMENSIONS'
       include 'DIMENSIONS.ZSCOPT'
+      include 'DIMENSIONS.FREE'
       include 'COMMON.VAR'
       include 'COMMON.GEO'
       include 'COMMON.LOCAL'
@@ -4532,26 +5695,49 @@ C Set lprn=.true. for debugging
 c      lprn=.true.
 c      write (iout,*) "EBACK_SC_COR",iphi_start,iphi_end,nterm_sccor
       esccor=0.0D0
-      do i=iphi_start,iphi_end
-        if (itype(i-2).eq.21 .or. itype(i-1).eq.21) cycle
+      do i=itau_start,itau_end
+        if ((itype(i-2).eq.ntyp1).or.(itype(i-1).eq.ntyp1)) cycle
         esccor_ii=0.0D0
-        itori=itype(i-2)
-        itori1=itype(i-1)
+        isccori=isccortyp(itype(i-2))
+        isccori1=isccortyp(itype(i-1))
         phii=phi(i)
+        do intertyp=1,3 !intertyp
+cc Added 09 May 2012 (Adasko)
+cc  Intertyp means interaction type of backbone mainchain correlation: 
+c   1 = SC...Ca...Ca...Ca
+c   2 = Ca...Ca...Ca...SC
+c   3 = SC...Ca...Ca...SCi
         gloci=0.0D0
-        do j=1,nterm_sccor
-          v1ij=v1sccor(j,itori,itori1)
-          v2ij=v2sccor(j,itori,itori1)
-          cosphi=dcos(j*phii)
-          sinphi=dsin(j*phii)
-          esccor=esccor+v1ij*cosphi+v2ij*sinphi
-          gloci=gloci+j*(v2ij*cosphi-v1ij*sinphi)
-        enddo
+        if (((intertyp.eq.3).and.((itype(i-2).eq.10).or.
+     &      (itype(i-1).eq.10).or.(itype(i-2).eq.ntyp1).or.
+     &      (itype(i-1).eq.ntyp1)))
+     &    .or. ((intertyp.eq.1).and.((itype(i-2).eq.10)
+     &     .or.(itype(i-2).eq.ntyp1).or.(itype(i-1).eq.ntyp1)
+     &     .or.(itype(i).eq.ntyp1)))
+     &    .or.((intertyp.eq.2).and.((itype(i-1).eq.10).or.
+     &      (itype(i-1).eq.ntyp1).or.(itype(i-2).eq.ntyp1).or.
+     &      (itype(i-3).eq.ntyp1)))) cycle
+        if ((intertyp.eq.2).and.(i.eq.4).and.(itype(1).eq.ntyp1)) cycle
+        if ((intertyp.eq.1).and.(i.eq.nres).and.(itype(nres).eq.ntyp1))
+     & cycle
+       do j=1,nterm_sccor(isccori,isccori1)
+          v1ij=v1sccor(j,intertyp,isccori,isccori1)
+          v2ij=v2sccor(j,intertyp,isccori,isccori1)
+          cosphi=dcos(j*tauangle(intertyp,i))
+          sinphi=dsin(j*tauangle(intertyp,i))
+           esccor=esccor+v1ij*cosphi+v2ij*sinphi
+           gloci=gloci+j*(v2ij*cosphi-v1ij*sinphi)
+         enddo
+c      write (iout,*) "EBACK_SC_COR",i,v1ij*cosphi+v2ij*sinphi,intertyp,
+c     & nterm_sccor(isccori,isccori1),isccori,isccori1
+c        gloc_sc(intertyp,i-3,icg)=gloc_sc(intertyp,i-3,icg)+wsccor*gloci
         if (lprn)
      &  write (iout,'(2(a3,2x,i3,2x),2i3,6f8.3/26x,6f8.3/)')
      &  restyp(itype(i-2)),i-2,restyp(itype(i-1)),i-1,itori,itori1,
-     &  (v1sccor(j,itori,itori1),j=1,6),(v2sccor(j,itori,itori1),j=1,6)
-        gsccor_loc(i-3)=gloci
+     &  (v1sccor(j,1,itori,itori1),j=1,6)
+     &  ,(v2sccor(j,1,itori,itori1),j=1,6)
+c        gsccor_loc(i-3)=gloci
+       enddo !intertyp
       enddo
       return
       end
@@ -4660,9 +5846,9 @@ c------------------------------------------------------------------------------
       integer dimen1,dimen2,atom,indx
       double precision buffer(dimen1,dimen2)
       double precision zapas 
-      common /contacts_hb/ zapas(3,20,maxres,7),
-     &   facont_hb(20,maxres),ees0p(20,maxres),ees0m(20,maxres),
-     &         num_cont_hb(maxres),jcont_hb(20,maxres)
+      common /contacts_hb/ zapas(3,ntyp,maxres,7),
+     &   facont_hb(ntyp,maxres),ees0p(ntyp,maxres),ees0m(ntyp,maxres),
+     &         num_cont_hb(maxres),jcont_hb(ntyp,maxres)
       num_kont=num_cont_hb(atom)
       do i=1,num_kont
         do k=1,7
@@ -4685,9 +5871,10 @@ c------------------------------------------------------------------------------
       integer dimen1,dimen2,atom,indx
       double precision buffer(dimen1,dimen2)
       double precision zapas 
-      common /contacts_hb/ zapas(3,20,maxres,7),
-     &         facont_hb(20,maxres),ees0p(20,maxres),ees0m(20,maxres),
-     &         num_cont_hb(maxres),jcont_hb(20,maxres)
+      common /contacts_hb/ zapas(3,ntyp,maxres,7),
+     &         facont_hb(ntyp,maxres),ees0p(ntyp,maxres),
+     &         ees0m(ntyp,maxres),
+     &         num_cont_hb(maxres),jcont_hb(ntyp,maxres)
       num_kont=buffer(1,indx+26)
       num_kont_old=num_cont_hb(atom)
       num_cont_hb(atom)=num_kont+num_kont_old
@@ -4920,6 +6107,7 @@ C This subroutine calculates multi-body contributions to hydrogen-bonding
 C Set lprn=.true. for debugging
       lprn=.false.
       eturn6=0.0d0
+      ecorr6=0.0d0
 #ifdef MPL
       n_corr=0
       n_corr1=0
@@ -5109,7 +6297,11 @@ cd     &          dabs(eello6(i,j,i+1,j1,jj,kk))
 cd                  write (iout,*) '******eturn6: i,j,i+1,j1',i,j,i+1,j1
                   eturn6=eturn6+eello_turn6(i,jj,kk)
 cd                  write (2,*) 'multibody_eello:eturn6',eturn6
+                 else if ((wturn6.eq.0.0d0).and.(wcorr6.eq.0.0d0)) then
+                   eturn6=0.0d0
+                   ecorr6=0.0d0
                 endif
+              
               ENDIF
 1111          continue
             else if (j1.eq.j) then
@@ -5130,6 +6322,7 @@ c             ecorr=ecorr+ehbcorr(i,j,i,j+1,jj,kk,0.60D0,-0.40D0)
           enddo ! kk
         enddo ! jj
       enddo ! i
+      write (iout,*) "eturn6",eturn6,ecorr6
       return
       end
 c------------------------------------------------------------------------------
@@ -6426,7 +7619,7 @@ c----------------------------------------------------------------------------
       include 'COMMON.GEO'
       logical swap
       double precision vv(2),pizda(2,2),auxmat(2,2),auxvec(2),
-     & auxvec1(2),auxvec2(1),auxmat1(2,2)
+     & auxvec1(2),auxvec2(2),auxmat1(2,2)
       logical lprn
       common /kutas/ lprn
 CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
@@ -7436,4 +8629,476 @@ C-----------------------------------------------------------------------------
       scalar=sc
       return
       end
+C-----------------------------------------------------------------------
+      double precision function sscale(r)
+      double precision r,gamm
+      include "COMMON.SPLITELE"
+      if(r.lt.r_cut-rlamb) then
+        sscale=1.0d0
+      else if(r.le.r_cut.and.r.ge.r_cut-rlamb) then
+        gamm=(r-(r_cut-rlamb))/rlamb
+        sscale=1.0d0+gamm*gamm*(2*gamm-3.0d0)
+      else
+        sscale=0d0
+      endif
+      return
+      end
+C-----------------------------------------------------------------------
+C-----------------------------------------------------------------------
+      double precision function sscagrad(r)
+      double precision r,gamm
+      include "COMMON.SPLITELE"
+      if(r.lt.r_cut-rlamb) then
+        sscagrad=0.0d0
+      else if(r.le.r_cut.and.r.ge.r_cut-rlamb) then
+        gamm=(r-(r_cut-rlamb))/rlamb
+        sscagrad=gamm*(6*gamm-6.0d0)/rlamb
+      else
+        sscagrad=0.0d0
+      endif
+      return
+      end
+C-----------------------------------------------------------------------
+C-----------------------------------------------------------------------
+      double precision function sscalelip(r)
+      double precision r,gamm
+      include "COMMON.SPLITELE"
+C      if(r.lt.r_cut-rlamb) then
+C        sscale=1.0d0
+C      else if(r.le.r_cut.and.r.ge.r_cut-rlamb) then
+C        gamm=(r-(r_cut-rlamb))/rlamb
+        sscalelip=1.0d0+r*r*(2*r-3.0d0)
+C      else
+C        sscale=0d0
+C      endif
+      return
+      end
+C-----------------------------------------------------------------------
+      double precision function sscagradlip(r)
+      double precision r,gamm
+      include "COMMON.SPLITELE"
+C     if(r.lt.r_cut-rlamb) then
+C        sscagrad=0.0d0
+C      else if(r.le.r_cut.and.r.ge.r_cut-rlamb) then
+C        gamm=(r-(r_cut-rlamb))/rlamb
+        sscagradlip=r*(6*r-6.0d0)
+C      else
+C        sscagrad=0.0d0
+C      endif
+      return
+      end
+c----------------------------------------------------------------------------
+      double precision function sscale2(r,r_cut,r0,rlamb)
+      implicit none
+      double precision r,gamm,r_cut,r0,rlamb,rr
+      rr = dabs(r-r0)
+c      write (2,*) "r",r," r_cut",r_cut," r0",r0," rlamb",rlamb
+c      write (2,*) "rr",rr
+      if(rr.lt.r_cut-rlamb) then
+        sscale2=1.0d0
+      else if(rr.le.r_cut.and.rr.ge.r_cut-rlamb) then
+        gamm=(rr-(r_cut-rlamb))/rlamb
+        sscale2=1.0d0+gamm*gamm*(2*gamm-3.0d0)
+      else
+        sscale2=0d0
+      endif
+      return
+      end
+C-----------------------------------------------------------------------
+      double precision function sscalgrad2(r,r_cut,r0,rlamb)
+      implicit none
+      double precision r,gamm,r_cut,r0,rlamb,rr
+      rr = dabs(r-r0)
+      if(rr.lt.r_cut-rlamb) then
+        sscalgrad2=0.0d0
+      else if(rr.le.r_cut.and.rr.ge.r_cut-rlamb) then
+        gamm=(rr-(r_cut-rlamb))/rlamb
+        if (r.ge.r0) then
+          sscalgrad2=gamm*(6*gamm-6.0d0)/rlamb
+        else
+          sscalgrad2=-gamm*(6*gamm-6.0d0)/rlamb
+        endif
+      else
+        sscalgrad2=0.0d0
+      endif
+      return
+      end
+c----------------------------------------------------------------------------
+      subroutine e_saxs(Esaxs_constr)
+      implicit none
+      include 'DIMENSIONS'
+      include 'DIMENSIONS.ZSCOPT'
+      include 'DIMENSIONS.FREE'
+#ifdef MPI
+      include "mpif.h"
+      include "COMMON.SETUP"
+      integer IERR
+#endif
+      include 'COMMON.SBRIDGE'
+      include 'COMMON.CHAIN'
+      include 'COMMON.GEO'
+      include 'COMMON.LOCAL'
+      include 'COMMON.INTERACT'
+      include 'COMMON.VAR'
+      include 'COMMON.IOUNITS'
+      include 'COMMON.DERIV'
+      include 'COMMON.CONTROL'
+      include 'COMMON.NAMES'
+      include 'COMMON.FFIELD'
+      include 'COMMON.LANGEVIN'
+c
+      double precision Esaxs_constr
+      integer i,iint,j,k,l
+      double precision PgradC(maxSAXS,3,maxres),
+     &  PgradX(maxSAXS,3,maxres),Pcalc(maxSAXS)
+#ifdef MPI
+      double precision PgradC_(maxSAXS,3,maxres),
+     &  PgradX_(maxSAXS,3,maxres),Pcalc_(maxSAXS)
+#endif
+      double precision dk,dijCACA,dijCASC,dijSCCA,dijSCSC,
+     & sigma2CACA,sigma2CASC,sigma2SCCA,sigma2SCSC,expCACA,expCASC,
+     & expSCCA,expSCSC,CASCgrad,SCCAgrad,SCSCgrad,aux,auxC,auxC1,
+     & auxX,auxX1,CACAgrad,Cnorm
+      double precision sss2,ssgrad2,rrr,sscalgrad2,sscale2
+      double precision dist
+      external dist
+c  SAXS restraint penalty function
+#ifdef DEBUG
+      write(iout,*) "------- SAXS penalty function start -------"
+      write (iout,*) "nsaxs",nsaxs
+      write (iout,*) "Esaxs: iatsc_s",iatsc_s," iatsc_e",iatsc_e
+      write (iout,*) "Psaxs"
+      do i=1,nsaxs
+        write (iout,'(i5,e15.5)') i, Psaxs(i)
+      enddo
+#endif
+      Esaxs_constr = 0.0d0
+      do k=1,nsaxs
+        Pcalc(k)=0.0d0
+        do j=1,nres
+          do l=1,3
+            PgradC(k,l,j)=0.0d0
+            PgradX(k,l,j)=0.0d0
+          enddo
+        enddo
+      enddo
+      do i=iatsc_s,iatsc_e
+       if (itype(i).eq.ntyp1) cycle
+       do iint=1,nint_gr(i)
+         do j=istart(i,iint),iend(i,iint)
+           if (itype(j).eq.ntyp1) cycle
+#ifdef ALLSAXS
+           dijCACA=dist(i,j)
+           dijCASC=dist(i,j+nres)
+           dijSCCA=dist(i+nres,j)
+           dijSCSC=dist(i+nres,j+nres)
+           sigma2CACA=2.0d0/(pstok**2)
+           sigma2CASC=4.0d0/(pstok**2+restok(itype(j))**2)
+           sigma2SCCA=4.0d0/(pstok**2+restok(itype(i))**2)
+           sigma2SCSC=4.0d0/(restok(itype(j))**2+restok(itype(i))**2)
+           do k=1,nsaxs
+             dk = distsaxs(k)
+             expCACA = dexp(-0.5d0*sigma2CACA*(dijCACA-dk)**2)
+             if (itype(j).ne.10) then
+             expCASC = dexp(-0.5d0*sigma2CASC*(dijCASC-dk)**2)
+             else
+             endif
+             expCASC = 0.0d0
+             if (itype(i).ne.10) then
+             expSCCA = dexp(-0.5d0*sigma2SCCA*(dijSCCA-dk)**2)
+             else 
+             expSCCA = 0.0d0
+             endif
+             if (itype(i).ne.10 .and. itype(j).ne.10) then
+             expSCSC = dexp(-0.5d0*sigma2SCSC*(dijSCSC-dk)**2)
+             else
+             expSCSC = 0.0d0
+             endif
+             Pcalc(k) = Pcalc(k)+expCACA+expCASC+expSCCA+expSCSC
+#ifdef DEBUG
+             write(iout,*) "i j k Pcalc",i,j,Pcalc(k)
+#endif
+             CACAgrad = sigma2CACA*(dijCACA-dk)*expCACA
+             CASCgrad = sigma2CASC*(dijCASC-dk)*expCASC
+             SCCAgrad = sigma2SCCA*(dijSCCA-dk)*expSCCA
+             SCSCgrad = sigma2SCSC*(dijSCSC-dk)*expSCSC
+             do l=1,3
+c CA CA 
+               aux = CACAgrad*(C(l,j)-C(l,i))/dijCACA
+               PgradC(k,l,i) = PgradC(k,l,i)-aux
+               PgradC(k,l,j) = PgradC(k,l,j)+aux
+c CA SC
+               if (itype(j).ne.10) then
+               aux = CASCgrad*(C(l,j+nres)-C(l,i))/dijCASC
+               PgradC(k,l,i) = PgradC(k,l,i)-aux
+               PgradC(k,l,j) = PgradC(k,l,j)+aux
+               PgradX(k,l,j) = PgradX(k,l,j)+aux
+               endif
+c SC CA
+               if (itype(i).ne.10) then
+               aux = SCCAgrad*(C(l,j)-C(l,i+nres))/dijSCCA
+               PgradX(k,l,i) = PgradX(k,l,i)-aux
+               PgradC(k,l,i) = PgradC(k,l,i)-aux
+               PgradC(k,l,j) = PgradC(k,l,j)+aux
+               endif
+c SC SC
+               if (itype(i).ne.10 .and. itype(j).ne.10) then
+               aux = SCSCgrad*(C(l,j+nres)-C(l,i+nres))/dijSCSC
+               PgradC(k,l,i) = PgradC(k,l,i)-aux
+               PgradC(k,l,j) = PgradC(k,l,j)+aux
+               PgradX(k,l,i) = PgradX(k,l,i)-aux
+               PgradX(k,l,j) = PgradX(k,l,j)+aux
+               endif
+             enddo ! l
+           enddo ! k
+#else
+           dijCACA=dist(i,j)
+           sigma2CACA=scal_rad**2*0.25d0/
+     &        (restok(itype(j))**2+restok(itype(i))**2)
 
+           IF (saxs_cutoff.eq.0) THEN
+           do k=1,nsaxs
+             dk = distsaxs(k)
+             expCACA = dexp(-0.5d0*sigma2CACA*(dijCACA-dk)**2)
+             Pcalc(k) = Pcalc(k)+expCACA
+             CACAgrad = sigma2CACA*(dijCACA-dk)*expCACA
+             do l=1,3
+               aux = CACAgrad*(C(l,j)-C(l,i))/dijCACA
+               PgradC(k,l,i) = PgradC(k,l,i)-aux
+               PgradC(k,l,j) = PgradC(k,l,j)+aux
+             enddo ! l
+           enddo ! k
+           ELSE
+           rrr = saxs_cutoff*2.0d0/dsqrt(sigma2CACA)
+           do k=1,nsaxs
+             dk = distsaxs(k)
+c             write (2,*) "ijk",i,j,k
+             sss2 = sscale2(dijCACA,rrr,dk,0.3d0)
+             if (sss2.eq.0.0d0) cycle
+             ssgrad2 = sscalgrad2(dijCACA,rrr,dk,0.3d0)
+             expCACA = dexp(-0.5d0*sigma2CACA*(dijCACA-dk)**2)*sss2
+             Pcalc(k) = Pcalc(k)+expCACA
+#ifdef DEBUG
+             write(iout,*) "i j k Pcalc",i,j,Pcalc(k)
+#endif
+             CACAgrad = -sigma2CACA*(dijCACA-dk)*expCACA+
+     &             ssgrad2*expCACA/sss2
+             do l=1,3
+c CA CA 
+               aux = CACAgrad*(C(l,j)-C(l,i))/dijCACA
+               PgradC(k,l,i) = PgradC(k,l,i)+aux
+               PgradC(k,l,j) = PgradC(k,l,j)-aux
+             enddo ! l
+           enddo ! k
+           ENDIF
+#endif
+         enddo ! j
+       enddo ! iint
+      enddo ! i
+#ifdef MPI
+      if (nfgtasks.gt.1) then 
+        call MPI_Reduce(Pcalc(1),Pcalc_(1),nsaxs,MPI_DOUBLE_PRECISION,
+     &    MPI_SUM,king,FG_COMM,IERR)
+        if (fg_rank.eq.king) then
+          do k=1,nsaxs
+            Pcalc(k) = Pcalc_(k)
+          enddo
+        endif
+        call MPI_Reduce(PgradC(k,1,1),PgradC_(k,1,1),3*maxsaxs*nres,
+     &    MPI_DOUBLE_PRECISION,MPI_SUM,king,FG_COMM,IERR)
+        if (fg_rank.eq.king) then
+          do i=1,nres
+            do l=1,3
+              do k=1,nsaxs
+                PgradC(k,l,i) = PgradC_(k,l,i)
+              enddo
+            enddo
+          enddo
+        endif
+#ifdef ALLSAXS
+        call MPI_Reduce(PgradX(k,1,1),PgradX_(k,1,1),3*maxsaxs*nres,
+     &    MPI_DOUBLE_PRECISION,MPI_SUM,king,FG_COMM,IERR)
+        if (fg_rank.eq.king) then
+          do i=1,nres
+            do l=1,3
+              do k=1,nsaxs
+                PgradX(k,l,i) = PgradX_(k,l,i)
+              enddo
+            enddo
+          enddo
+        endif
+#endif
+      endif
+#endif
+#ifdef MPI
+      if (fg_rank.eq.king) then
+#endif
+      Cnorm = 0.0d0
+      do k=1,nsaxs
+        Cnorm = Cnorm + Pcalc(k)
+      enddo
+      Esaxs_constr = dlog(Cnorm)-wsaxs0
+      do k=1,nsaxs
+        if (Pcalc(k).gt.0.0d0) 
+     &  Esaxs_constr = Esaxs_constr - Psaxs(k)*dlog(Pcalc(k)) 
+#ifdef DEBUG
+        write (iout,*) "k",k," Esaxs_constr",Esaxs_constr
+#endif
+      enddo
+#ifdef DEBUG
+      write (iout,*) "Cnorm",Cnorm," Esaxs_constr",Esaxs_constr
+#endif
+      do i=nnt,nct
+        do l=1,3
+          auxC=0.0d0
+          auxC1=0.0d0
+          auxX=0.0d0
+          auxX1=0.d0 
+          do k=1,nsaxs
+            if (Pcalc(k).gt.0) 
+     &      auxC  = auxC +Psaxs(k)*PgradC(k,l,i)/Pcalc(k)
+            auxC1 = auxC1+PgradC(k,l,i)
+#ifdef ALLSAXS
+            auxX  = auxX +Psaxs(k)*PgradX(k,l,i)/Pcalc(k)
+            auxX1 = auxX1+PgradX(k,l,i)
+#endif
+          enddo
+          gsaxsC(l,i) = auxC - auxC1/Cnorm
+#ifdef ALLSAXS
+          gsaxsX(l,i) = auxX - auxX1/Cnorm
+#endif
+c          write (iout,*) "l i",l,i," gradC",wsaxs*(auxC - auxC1/Cnorm),
+c     *     " gradX",wsaxs*(auxX - auxX1/Cnorm)
+        enddo
+      enddo
+#ifdef MPI
+      endif
+#endif
+      return
+      end
+c----------------------------------------------------------------------------
+      subroutine e_saxsC(Esaxs_constr)
+      implicit none
+      include 'DIMENSIONS'
+      include 'DIMENSIONS.ZSCOPT'
+      include 'DIMENSIONS.FREE'
+#ifdef MPI
+      include "mpif.h"
+      include "COMMON.SETUP"
+      integer IERR
+#endif
+      include 'COMMON.SBRIDGE'
+      include 'COMMON.CHAIN'
+      include 'COMMON.GEO'
+      include 'COMMON.LOCAL'
+      include 'COMMON.INTERACT'
+      include 'COMMON.VAR'
+      include 'COMMON.IOUNITS'
+      include 'COMMON.DERIV'
+      include 'COMMON.CONTROL'
+      include 'COMMON.NAMES'
+      include 'COMMON.FFIELD'
+      include 'COMMON.LANGEVIN'
+c
+      double precision Esaxs_constr
+      integer i,iint,j,k,l
+      double precision PgradC(3,maxres),PgradX(3,maxres),Pcalc,logPtot
+#ifdef MPI
+      double precision gsaxsc_(3,maxres),gsaxsx_(3,maxres),logPtot_
+#endif
+      double precision dk,dijCASPH,dijSCSPH,
+     & sigma2CA,sigma2SC,expCASPH,expSCSPH,
+     & CASPHgrad,SCSPHgrad,aux,auxC,auxC1,
+     & auxX,auxX1,Cnorm
+c  SAXS restraint penalty function
+#ifdef DEBUG
+      write(iout,*) "------- SAXS penalty function start -------"
+      write (iout,*) "nsaxs",nsaxs," isaxs_start",isaxs_start,
+     & " isaxs_end",isaxs_end
+      write (iout,*) "nnt",nnt," ntc",nct
+      do i=nnt,nct
+        write(iout,'(a6,i5,3f10.5,5x,2f10.5)')
+     &    "CA",i,(C(j,i),j=1,3),pstok,restok(itype(i))
+      enddo
+      do i=nnt,nct
+        write(iout,'(a6,i5,3f10.5)')"CSaxs",i,(Csaxs(j,i),j=1,3)
+      enddo
+#endif
+      Esaxs_constr = 0.0d0
+      logPtot=0.0d0
+      do j=isaxs_start,isaxs_end
+        Pcalc=0.0d0
+        do i=1,nres
+          do l=1,3
+            PgradC(l,i)=0.0d0
+            PgradX(l,i)=0.0d0
+          enddo
+        enddo
+        do i=nnt,nct
+          dijCASPH=0.0d0
+          dijSCSPH=0.0d0
+          do l=1,3
+            dijCASPH=dijCASPH+(C(l,i)-Csaxs(l,j))**2
+          enddo
+          if (itype(i).ne.10) then
+          do l=1,3
+            dijSCSPH=dijSCSPH+(C(l,i+nres)-Csaxs(l,j))**2
+          enddo
+          endif
+          sigma2CA=2.0d0/pstok**2
+          sigma2SC=4.0d0/restok(itype(i))**2
+          expCASPH = dexp(-0.5d0*sigma2CA*dijCASPH)
+          expSCSPH = dexp(-0.5d0*sigma2SC*dijSCSPH)
+          Pcalc = Pcalc+expCASPH+expSCSPH
+#ifdef DEBUG
+          write(*,*) "processor i j Pcalc",
+     &       MyRank,i,j,dijCASPH,dijSCSPH, Pcalc
+#endif
+          CASPHgrad = sigma2CA*expCASPH
+          SCSPHgrad = sigma2SC*expSCSPH
+          do l=1,3
+            aux = (C(l,i+nres)-Csaxs(l,j))*SCSPHgrad
+            PgradX(l,i) = PgradX(l,i) + aux
+            PgradC(l,i) = PgradC(l,i)+(C(l,i)-Csaxs(l,j))*CASPHgrad+aux
+          enddo ! l
+        enddo ! i
+        do i=nnt,nct
+          do l=1,3
+            gsaxsc(l,i)=gsaxsc(l,i)+PgradC(l,i)/Pcalc
+            gsaxsx(l,i)=gsaxsx(l,i)+PgradX(l,i)/Pcalc
+          enddo
+        enddo
+        logPtot = logPtot - dlog(Pcalc) 
+c        print *,"me",me,MyRank," j",j," logPcalc",-dlog(Pcalc),
+c     &    " logPtot",logPtot
+      enddo ! j
+#ifdef MPI
+      if (nfgtasks.gt.1) then 
+c        write (iout,*) "logPtot before reduction",logPtot
+        call MPI_Reduce(logPtot,logPtot_,1,MPI_DOUBLE_PRECISION,
+     &    MPI_SUM,king,FG_COMM,IERR)
+        logPtot = logPtot_
+c        write (iout,*) "logPtot after reduction",logPtot
+        call MPI_Reduce(gsaxsC(1,1),gsaxsC_(1,1),3*nres,
+     &    MPI_DOUBLE_PRECISION,MPI_SUM,king,FG_COMM,IERR)
+        if (fg_rank.eq.king) then
+          do i=1,nres
+            do l=1,3
+              gsaxsC(l,i) = gsaxsC_(l,i)
+            enddo
+          enddo
+        endif
+        call MPI_Reduce(gsaxsX(1,1),gsaxsX_(1,1),3*nres,
+     &    MPI_DOUBLE_PRECISION,MPI_SUM,king,FG_COMM,IERR)
+        if (fg_rank.eq.king) then
+          do i=1,nres
+            do l=1,3
+              gsaxsX(l,i) = gsaxsX_(l,i)
+            enddo
+          enddo
+        endif
+      endif
+#endif
+      Esaxs_constr = logPtot
+      return
+      end