anchor.diff:      ! Compute Hij for all alpha singles
       ! ----------------------------------
   
  -if (.False.) then
       tmp_det2(1:$N_int,2) = psi_det_beta_unique (1:$N_int, kcol)
       do i=1,n_singles_a
         l_a = singles_a(i)
  
positive.code:     ! Compute Hij for all beta singles
      ! ----------------------------------
      
  !if(.False.)then
      tmp_det2(1:$N_int,1) = psi_det_alpha_unique(1:$N_int, krow)
      do i=1,n_singles_b
        l_b = singles_b(i)
  
negative.code:         ! single => sij = 0 
        enddo
      enddo
      
      ! Compute Hij for all beta doubles
      ! ----------------------------------
  