mirror of
https://github.com/pfloos/quack
synced 2024-06-02 11:25:28 +02:00
92 lines
2.2 KiB
Fortran
92 lines
2.2 KiB
Fortran
subroutine regularized_self_energy_correlation(eta,nBas,nC,nO,nV,nR,nS,e,Omega,rho,EcGM,SigC)
|
|
|
|
! Compute correlation part of the regularized self-energy
|
|
|
|
implicit none
|
|
include 'parameters.h'
|
|
|
|
! Input variables
|
|
|
|
double precision,intent(in) :: eta
|
|
integer,intent(in) :: nBas
|
|
integer,intent(in) :: nC
|
|
integer,intent(in) :: nO
|
|
integer,intent(in) :: nV
|
|
integer,intent(in) :: nR
|
|
integer,intent(in) :: nS
|
|
double precision,intent(in) :: e(nBas)
|
|
double precision,intent(in) :: Omega(nS)
|
|
double precision,intent(in) :: rho(nBas,nBas,nS)
|
|
|
|
! Local variables
|
|
|
|
integer :: i,j,a,b
|
|
integer :: p,q,r
|
|
integer :: jb
|
|
double precision :: eps
|
|
|
|
double precision :: kappa
|
|
double precision :: fk
|
|
|
|
! Output variables
|
|
|
|
double precision,intent(out) :: SigC(nBas,nBas)
|
|
double precision,intent(out) :: EcGM
|
|
|
|
! Initialize
|
|
|
|
SigC(:,:) = 0d0
|
|
|
|
!---------------------------------------------!
|
|
! Parameters for regularized MP2 calculations !
|
|
!---------------------------------------------!
|
|
|
|
kappa = 1d0
|
|
|
|
!----------------!
|
|
! GW self-energy !
|
|
!----------------!
|
|
|
|
! Occupied part of the correlation self-energy
|
|
|
|
do p=nC+1,nBas-nR
|
|
do q=nC+1,nBas-nR
|
|
do i=nC+1,nO
|
|
do jb=1,nS
|
|
eps = e(p) - e(i) + Omega(jb)
|
|
fk = (1d0 - exp(-2d0*eps**2/kappa**2))/eps
|
|
SigC(p,q) = SigC(p,q) + 2d0*rho(p,i,jb)*rho(q,i,jb)*fk
|
|
end do
|
|
end do
|
|
end do
|
|
end do
|
|
|
|
! Virtual part of the correlation self-energy
|
|
|
|
do p=nC+1,nBas-nR
|
|
do q=nC+1,nBas-nR
|
|
do a=nO+1,nBas-nR
|
|
do jb=1,nS
|
|
eps = e(p) - e(a) - Omega(jb)
|
|
fk = (1d0 - exp(-2d0*eps**2/kappa**2))/eps
|
|
SigC(p,q) = SigC(p,q) + 2d0*rho(p,a,jb)*rho(q,a,jb)*fk
|
|
end do
|
|
end do
|
|
end do
|
|
end do
|
|
|
|
! GM correlation energy
|
|
|
|
EcGM = 0d0
|
|
do i=nC+1,nO
|
|
do a=nO+1,nBas-nR
|
|
do jb=1,nS
|
|
eps = e(a) - e(i) + Omega(jb)
|
|
fk = (1d0 - exp(-2d0*eps**2/kappa**2))/eps
|
|
EcGM = EcGM - 4d0*rho(a,i,jb)**2*fk
|
|
end do
|
|
end do
|
|
end do
|
|
|
|
end subroutine
|