source/unres/src_MD/src/md-diff/np/tnp_respa_step1.f

   1 c-----------------------------------------------------------------
   2       subroutine tnp_respa_step1
   3 c Applying Nose-Poincare algorithm - step 1 to vel for RESPA
   4 c J.Comput.Phys. 151 114 (1999) S.D.Bond B.J.Leimkuhler B.B.Laird
   5 c
   6 c d_t is not updated here, it is destroyed
   7 c
   8       implicit real*8 (a-h,o-z)
   9       include 'DIMENSIONS'
  10       include 'COMMON.CONTROL'
  11       include 'COMMON.VAR'
  12       include 'COMMON.MD'
  13       include 'COMMON.CHAIN'
  14       include 'COMMON.DERIV'
  15       include 'COMMON.GEO'
  16       include 'COMMON.LOCAL'
  17       include 'COMMON.INTERACT'
  18       include 'COMMON.IOUNITS'
  19       include 'COMMON.NAMES'
  20       double precision C_np,d_time_s,tmp,d_time_ss
  21       double precision energia(0:n_ene)
  22
  23       d_time_s=d_time*0.5*s_np
  24
  25       do j=1,3
  26         d_t_old(j,0)=d_t_old(j,0)+d_a(j,0)*d_time_s
  27       enddo
  28       do i=nnt,nct-1
  29         do j=1,3
  30           d_t_old(j,i)=d_t_old(j,i)+d_a(j,i)*d_time_s
  31         enddo
  32       enddo
  33       do i=nnt,nct
  34         if (itype(i).ne.10) then
  35           inres=i+nres
  36           do j=1,3
  37            d_t_old(j,inres)=d_t_old(j,inres)+d_a(j,inres)*d_time_s
  38           enddo
  39         endif
  40       enddo
  41
  42
  43 c      C_np=0.5*d_time*(dimen*Rb*t_bath*(1.0+log(s_np))-EK+potE-H0)
  44 c     &                     -pi_np
  45 c
  46 c      pistar=-2.0*C_np/(1.0+sqrt(1.0-C_np*d_time/Q_np))
  47 c      tmp=0.5*d_time*pistar/Q_np
  48 c      s12_np=s_np*(1.0+tmp)/(1.0-tmp)
  49 c      write(iout,*) 'tnp_respa_step1',s_np,s12_np,EK,potE,C_np,pistar,tmp
  50
  51 ct1      pi_np=pistar
  52 c      sold_np=s_np
  53 c      s_np=s12_np
  54
  55 c-------------------------------------
  56 c test of reviewer's comment
  57        pi_np=pi_np-0.5*d_time*(E_long+Csplit-H0)
  58 cr       print '(a,3f)','1 pi_np,s_np',pi_np,s_np,E_long
  59 c-------------------------------------
  60
  61       return
  62       end