mirror of
https://github.com/pfloos/quack
synced 2024-11-13 09:34:04 +01:00
76 lines
1.6 KiB
Fortran
76 lines
1.6 KiB
Fortran
subroutine renormalization_factor(COHSEX,eta,nBas,nC,nO,nV,nR,nS,e,Omega,rho,Z)
|
|
|
|
! Compute renormalization factor for GW
|
|
|
|
implicit none
|
|
include 'parameters.h'
|
|
|
|
! Input variables
|
|
|
|
logical,intent(in) :: COHSEX
|
|
double precision,intent(in) :: eta
|
|
integer,intent(in) :: nBas,nC,nO,nV,nR,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,x,jb
|
|
double precision :: eps
|
|
|
|
! Output variables
|
|
|
|
double precision,intent(out) :: Z(nBas)
|
|
|
|
! Initialize
|
|
|
|
Z(:) = 0d0
|
|
|
|
! static COHSEX approximation
|
|
|
|
if(COHSEX) then
|
|
|
|
Z(:) = 1d0
|
|
return
|
|
|
|
else
|
|
|
|
! Occupied part of the correlation self-energy
|
|
|
|
do x=nC+1,nBas-nR
|
|
do i=nC+1,nO
|
|
jb = 0
|
|
do j=nC+1,nO
|
|
do b=nO+1,nBas-nR
|
|
jb = jb + 1
|
|
eps = e(x) - e(i) + Omega(jb)
|
|
Z(x) = Z(x) - 2d0*rho(x,i,jb)**2*(eps/(eps**2 + eta**2))**2
|
|
end do
|
|
end do
|
|
end do
|
|
end do
|
|
|
|
! Virtual part of the correlation self-energy
|
|
|
|
do x=nC+1,nBas-nR
|
|
do a=nO+1,nBas-nR
|
|
jb = 0
|
|
do j=nC+1,nO
|
|
do b=nO+1,nBas-nR
|
|
jb = jb + 1
|
|
eps = e(x) - e(a) - Omega(jb)
|
|
Z(x) = Z(x) - 2d0*rho(x,a,jb)**2*(eps/(eps**2 + eta**2))**2
|
|
end do
|
|
end do
|
|
end do
|
|
end do
|
|
|
|
end if
|
|
|
|
! Compute renormalization factor from derivative of SigC
|
|
|
|
Z(:) = 1d0/(1d0 - Z(:))
|
|
|
|
end subroutine renormalization_factor
|