Removed memory bottleneck in CISD SC2

src/CISD_SC2_selected/cisd_sc2_selection.irp.f

@@ -64,9 +64,8 @@ program cisd_sc2_selected
     endif
   enddo
   N_det = min(n_det_max_cisd_sc2,N_det)
-  touch N_det psi_det psi_coef
   davidson_threshold = 1.d-10
-  touch davidson_threshold davidson_criterion
+  touch N_det psi_det psi_coef davidson_threshold davidson_criterion
   call diagonalize_CI_SC2
   pt2 = 0.d0
   if(do_pt2_end)then

src/Dets/SC2.irp.f

@@ -38,20 +38,8 @@ subroutine CISD_SC2(dets_in,u_in,energies,dim_in,sze,N_st,Nint,convergence)
   integer,allocatable            :: degree_exc(:), index_double(:)
   integer                        :: i_ok
   double precision,allocatable   :: e_corr_array(:),H_jj_ref(:),H_jj_dressed(:),hij_double(:)
-  double precision, allocatable  :: eigenvectors(:,:), eigenvalues(:),H_matrix_tmp(:,:)
   integer(bit_kind), allocatable :: doubles(:,:,:)
-  integer ,parameter             :: sze_max = 1000
 
-  if(sze.le.sze_max)then
-   allocate (eigenvectors(size(H_matrix_all_dets,1),sze))
-   allocate (H_matrix_tmp(size(H_matrix_all_dets,1),sze))
-   allocate (eigenvalues(sze))
-   do i = 1, sze
-    do j = 1, sze
-     H_matrix_tmp(i,j) = H_matrix_all_dets(i,j)
-    enddo
-   enddo
-  endif
   
   allocate (doubles(Nint,2,sze),e_corr_array(sze),H_jj_ref(sze),H_jj_dressed(sze),&
       index_double(sze), degree_exc(sze), hij_double(sze))
@@ -166,10 +154,14 @@ subroutine CISD_SC2(dets_in,u_in,energies,dim_in,sze,N_st,Nint,convergence)
     !$OMP END DO
     !$OMP END PARALLEL
     
-    PROVIDE n_states_diag h_matrix_all_dets
-    if(sze>sze_max)then
-     call davidson_diag_hjj(dets_in,u_in,H_jj_dressed,energies,dim_in,sze,N_st,Nint,output_Dets)
-    else
+    if(sze<=N_det_max_jacobi)then
+      double precision, allocatable  :: eigenvectors(:,:), eigenvalues(:),H_matrix_tmp(:,:)
+      allocate (H_matrix_tmp(size(H_matrix_all_dets,1),sze),eigenvalues(sze),eigenvectors(size(H_matrix_all_dets,1),sze))
+      do j=1,sze
+        do i=1,sze
+          H_matrix_tmp(i,j) = H_matrix_all_dets(i,j)
+        enddo
+      enddo
       do i = 1,sze
         H_matrix_tmp(i,i) = H_jj_dressed(i)
       enddo
@@ -181,6 +173,9 @@ subroutine CISD_SC2(dets_in,u_in,energies,dim_in,sze,N_st,Nint,convergence)
         enddo
         energies(j) = eigenvalues(j)
       enddo
+      deallocate (H_matrix_tmp, eigenvalues, eigenvectors)
+    else
+      call davidson_diag_hjj(dets_in,u_in,H_jj_dressed,energies,dim_in,sze,N_st,Nint,output_Dets)
     endif
     
     e_corr_double = 0.d0
@@ -217,51 +212,4 @@ subroutine CISD_SC2(dets_in,u_in,energies,dim_in,sze,N_st,Nint,convergence)
   
 end
 
-subroutine repeat_excitation(key_in,key_1,key_2,i_ok,Nint)
-  use bitmasks
-  implicit none
-  integer(bit_kind), intent(in)  :: key_in(Nint,2),key_1(Nint,2),key_2(Nint,2)
-  integer                        :: Nint
-  integer,intent(out)            :: i_ok
-  integer                        :: ispin,i_hole,k_hole,j_hole,i_particl,k_particl,j_particl,i_trou,degree,exc(0:2,2,2)
-  double precision               :: phase
-  i_ok = 1
-  call get_excitation(key_1,key_2,exc,degree,phase,Nint)
-  integer                        :: h1,p1,h2,p2,s1,s2
-  if(degree==2)then
-    call decode_exc(exc,degree,h1,p1,h2,p2,s1,s2)
-    !  first hole
-    k_hole = ishft(h1-1,-5)+1
-    j_hole = h1-ishft(k_hole-1,5)-1
-    if(iand(key_in(k_hole,s1),ibset(0,j_hole)).eq.0)then
-      i_ok = 0
-      return
-    endif
-    
-    !  second hole
-    k_hole = ishft(h2-1,-5)+1
-    j_hole = h2-ishft(k_hole-1,5)-1
-    if(iand(key_in(k_hole,s2),ibset(0,j_hole)).eq.0)then
-      i_ok = 0
-      return
-    endif
-    
-    ! first particle
-    k_particl  = ishft(p1-1,-5)+1
-    j_particl = p1-ishft(k_particl-1,5)-1
-    if(iand(key_in(k_particl,s1),ibset(0,j_particl)).ne.0)then
-      i_ok = 0
-      return
-    endif
-    
-    ! second particle
-    k_particl  = ishft(p2-1,-5)+1
-    j_particl = p2-ishft(k_particl-1,5)-1
-    if(iand(key_in(k_particl,s2),ibset(0,j_particl)).ne.0)then
-      i_ok = 0
-      return
-    endif
-    return
-  endif
-end
 

src/Dets/diagonalize_CI_SC2.irp.f

@@ -34,12 +34,10 @@ END_PROVIDER
   do j=1,N_states_diag
     do i=1,N_det
       CI_SC2_eigenvectors(i,j) = psi_coef(i,j)
-!     CI_SC2_eigenvectors(i,j) = CI_eigenvectors(i,j)
     enddo
     CI_SC2_electronic_energy(j) = CI_electronic_energy(j) 
   enddo
   
-  double precision :: convergence
   call CISD_SC2(psi_det,CI_SC2_eigenvectors,CI_SC2_electronic_energy, &
         size(CI_SC2_eigenvectors,1),N_det,N_states_diag,N_int,threshold_convergence_SC2)
 END_PROVIDER