mirror of
https://github.com/pfloos/quack
synced 2024-09-01 17:13:45 +02:00
92 lines
1.8 KiB
Fortran
92 lines
1.8 KiB
Fortran
|
subroutine linear_response_D_pp_od(ispin,nBas,nC,nO,nV,nR,nOO,nVV,lambda,ERI,D_pp)
|
||
|
|
||
|
! Compute the D matrix of the pp channel (without the diagonal term)
|
||
|
|
||
|
implicit none
|
||
|
include 'parameters.h'
|
||
|
|
||
|
! Input variables
|
||
|
|
||
|
integer,intent(in) :: ispin
|
||
|
integer,intent(in) :: nBas,nC,nO,nV,nR,nOO,nVV
|
||
|
double precision,intent(in) :: lambda
|
||
|
double precision,intent(in) :: ERI(nBas,nBas,nBas,nBas)
|
||
|
|
||
|
! Local variables
|
||
|
|
||
|
double precision,external :: Kronecker_delta
|
||
|
|
||
|
integer :: i,j,k,l,ij,kl
|
||
|
|
||
|
! Output variables
|
||
|
|
||
|
double precision,intent(out) :: D_pp(nOO,nOO)
|
||
|
|
||
|
! Build the D matrix for the singlet manifold
|
||
|
|
||
|
if(ispin == 1) then
|
||
|
|
||
|
ij = 0
|
||
|
do i=nC+1,nO
|
||
|
do j=i,nO
|
||
|
ij = ij + 1
|
||
|
kl = 0
|
||
|
do k=nC+1,nO
|
||
|
do l=k,nO
|
||
|
kl = kl + 1
|
||
|
|
||
|
D_pp(ij,kl) = lambda*(ERI(i,j,k,l) + ERI(i,j,l,k))/sqrt((1d0 + Kronecker_delta(i,j))*(1d0 + Kronecker_delta(k,l)))
|
||
|
|
||
|
end do
|
||
|
end do
|
||
|
end do
|
||
|
end do
|
||
|
|
||
|
end if
|
||
|
|
||
|
! Build the D matrix for the triplet manifold, the alpha-alpha block, or in the spin-orbital basis
|
||
|
|
||
|
if(ispin == 2 .or. ispin == 4) then
|
||
|
|
||
|
ij = 0
|
||
|
do i=nC+1,nO
|
||
|
do j=i+1,nO
|
||
|
ij = ij + 1
|
||
|
kl = 0
|
||
|
do k=nC+1,nO
|
||
|
do l=k+1,nO
|
||
|
kl = kl + 1
|
||
|
|
||
|
D_pp(ij,kl) = lambda*(ERI(i,j,k,l) - ERI(i,j,l,k))
|
||
|
|
||
|
end do
|
||
|
end do
|
||
|
end do
|
||
|
end do
|
||
|
|
||
|
end if
|
||
|
|
||
|
! Build the alpha-beta block of the D matrix
|
||
|
|
||
|
if(ispin == 3) then
|
||
|
|
||
|
ij = 0
|
||
|
do i=nC+1,nO
|
||
|
do j=nC+1,nO
|
||
|
ij = ij + 1
|
||
|
kl = 0
|
||
|
do k=nC+1,nO
|
||
|
do l=nC+1,nO
|
||
|
kl = kl + 1
|
||
|
|
||
|
D_pp(ij,kl) = lambda*ERI(i,j,k,l)
|
||
|
|
||
|
end do
|
||
|
end do
|
||
|
end do
|
||
|
end do
|
||
|
|
||
|
end if
|
||
|
|
||
|
end subroutine linear_response_D_pp_od
|