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mirror of https://github.com/pfloos/quack synced 2024-11-19 04:22:39 +01:00
quack/src/QuAcK/Bethe_Salpeter.f90

70 lines
2.3 KiB
Fortran

subroutine Bethe_Salpeter(TDA,singlet_manifold,triplet_manifold,eta, &
nBas,nC,nO,nV,nR,nS,ERI,eW,eGW,Omega,XpY,XmY,rho,EcRPA,EcBSE)
! Compute the Bethe-Salpeter excitation energies
implicit none
include 'parameters.h'
! Input variables
logical,intent(in) :: TDA
logical,intent(in) :: singlet_manifold
logical,intent(in) :: triplet_manifold
double precision,intent(in) :: eta
integer,intent(in) :: nBas,nC,nO,nV,nR,nS
double precision,intent(in) :: eW(nBas)
double precision,intent(in) :: eGW(nBas)
double precision,intent(in) :: ERI(nBas,nBas,nBas,nBas)
double precision :: Omega(nS,nspin)
double precision :: XpY(nS,nS,nspin)
double precision :: XmY(nS,nS,nspin)
double precision :: rho(nBas,nBas,nS,nspin)
! Local variables
integer :: ispin
! Output variables
double precision,intent(out) :: EcRPA(nspin)
double precision,intent(out) :: EcBSE(nspin)
! Singlet manifold
if(singlet_manifold) then
ispin = 1
EcBSE(ispin) = 0d0
call linear_response(ispin,.true.,TDA,.false.,eta,nBas,nC,nO,nV,nR,nS,1d0,eW,ERI, &
rho(:,:,:,ispin),EcRPA(ispin),Omega(:,ispin),XpY(:,:,ispin),XmY(:,:,ispin))
call excitation_density(nBas,nC,nO,nR,nS,ERI,XpY(:,:,ispin),rho(:,:,:,ispin))
call linear_response(ispin,.true.,TDA,.true.,eta,nBas,nC,nO,nV,nR,nS,1d0,eGW,ERI, &
rho(:,:,:,ispin),EcBSE(ispin),Omega(:,ispin),XpY(:,:,ispin),XmY(:,:,ispin))
call print_excitation('BSE ',ispin,nS,Omega(:,ispin))
end if
! Triplet manifold
if(triplet_manifold) then
ispin = 2
EcBSE(ispin) = 0d0
call linear_response(ispin,.true.,TDA,.false.,eta,nBas,nC,nO,nV,nR,nS,1d0,eW,ERI, &
rho(:,:,:,ispin),EcRPA(ispin),Omega(:,ispin),XpY(:,:,ispin),XmY(:,:,ispin))
call excitation_density(nBas,nC,nO,nR,nS,ERI,XpY(:,:,ispin),rho(:,:,:,ispin))
call linear_response(ispin,.true.,TDA,.true.,eta,nBas,nC,nO,nV,nR,nS,1d0,eGW,ERI, &
rho(:,:,:,ispin),EcBSE(ispin),Omega(:,ispin),XpY(:,:,ispin),XmY(:,:,ispin))
call print_excitation('BSE ',ispin,nS,Omega(:,ispin))
end if
end subroutine Bethe_Salpeter