SAXS cutoff correction

[unres.git] / source / unres / src_MD-M / energy_p_new_barrier.F

diff --git a/source/unres/src_MD-M/energy_p_new_barrier.F b/source/unres/src_MD-M/energy_p_new_barrier.F
index 7a158ed..ff2d579 100644 (file)
--- a/source/unres/src_MD-M/energy_p_new_barrier.F
+++ b/source/unres/src_MD-M/energy_p_new_barrier.F
@@ -11050,6 +11050,39 @@ C      print *,'AFM',Eafmforce,totTafm*velAFMconst,dist
       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
+        sscalgrad2=gamm*(6*gamm-6.0d0)/rlamb
+        if (r.lt.r0) sscalgrad2=-sscalgrad2
+      else
+        sscalgrad2=0.0d0
+      endif
+      return
+      end
+c----------------------------------------------------------------------------
       subroutine e_saxs(Esaxs_constr)
       implicit none
       include 'DIMENSIONS'
@@ -11084,6 +11117,7 @@ c
      & 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
@@ -11179,20 +11213,29 @@ c SC SC
            dijCACA=dist(i,j)
            sigma2CACA=scal_rad**2*0.25d0/
      &        (restok(itype(j))**2+restok(itype(i))**2)
+           rrr = 2.0d0/dsqrt(sigma2CACA)
            do k=1,nsaxs
              dk = distsaxs(k)
-             expCACA = dexp(-0.5d0*sigma2CACA*(dijCACA-dk)**2)
+c             write (2,*) "ijk",i,j,k
+             sss2 = sscale2(dijCACA,rrr,dk,0.3d0)
+             if (sss2.ne.0.0d0) then
+             ssgrad2 = sscalgrad2(dijCACA,rrr,dk,0.3d0)
+             if (energy_dec) write(iout,'(a4,3i5,4f10.4)') 
+     &          'saxs',i,j,k,dijCACA,rrr,dk,sss2
+             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
+             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
+             endif ! sss
            enddo ! k
 #endif
          enddo ! j