quack/src/GT/GTeh_self_energy_diag.f90

92 lines
2.0 KiB
Fortran

subroutine GTeh_self_energy_diag(eta,nBas,nC,nO,nV,nR,nS,e,Om,rhoL,rhoR,EcGM,Sig,Z)
! Compute diagonal of the correlation part of the self-energy and the renormalization factor
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) :: Om(nS)
double precision,intent(in) :: rhoL(nBas,nBas,nS)
double precision,intent(in) :: rhoR(nBas,nBas,nS)
! Local variables
integer :: i,a,p,m
double precision :: num,eps
! Output variables
double precision,intent(out) :: Sig(nBas)
double precision,intent(out) :: Z(nBas)
double precision,intent(out) :: EcGM
! Initialize
Sig(:) = 0d0
Z(:) = 0d0
!-----------------------------
! GW self-energy
!-----------------------------
! Occupied part of the correlation self-energy
do p=nC+1,nBas-nR
do i=nC+1,nO
do m=1,nS
eps = e(p) - e(i) + Om(m)
num = rhoL(i,p,m)*rhoR(i,p,m)
Sig(p) = Sig(p) + num*eps/(eps**2 + eta**2)
Z(p) = Z(p) - num*(eps**2 - eta**2)/(eps**2 + eta**2)**2
end do
end do
end do
! Virtual part of the correlation self-energy
do p=nC+1,nBas-nR
do a=nO+1,nBas-nR
do m=1,nS
eps = e(p) - e(a) - Om(m)
num = rhoL(p,a,m)*rhoR(p,a,m)
Sig(p) = Sig(p) + num*eps/(eps**2 + eta**2)
Z(p) = Z(p) - num*(eps**2 - eta**2)/(eps**2 + eta**2)**2
end do
end do
end do
! GM correlation energy
EcGM = 0d0
! do i=nC+1,nO
! do a=nO+1,nBas-nR
! do m=1,nS
! eps = e(a) - e(i) + Om(m)
! num = rhoL(i,a,m)*rhoR(i,a,m)
! EcGM = EcGM - num*eps/(eps**2 + eta**2)
! end do
! end do
! end do
! Compute renormalization factor from derivative
Z(:) = 1d0/(1d0 - Z(:))
end subroutine