10
1
mirror of https://github.com/pfloos/quack synced 2025-04-03 07:21:37 +02:00
QuAcK/src/GF/GGF2_phBSE.f90
2024-12-19 10:03:40 +01:00

70 lines
2.2 KiB
Fortran

subroutine GGF2_phBSE(TDA,dBSE,dTDA,eta,nBas,nC,nO,nV,nR,nS,ERI,dipole_int,eGF,EcBSE)
! Compute the second-order Bethe-Salpeter excitation energies
implicit none
include 'parameters.h'
! Input variables
logical,intent(in) :: TDA
logical,intent(in) :: dBSE
logical,intent(in) :: dTDA
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) :: eGF(nBas)
double precision,intent(in) :: ERI(nBas,nBas,nBas,nBas)
double precision,intent(in) :: dipole_int(nBas,nBas,ncart)
! Local variables
logical :: dRPA = .false.
double precision,allocatable :: OmBSE(:)
double precision,allocatable :: XpY(:,:)
double precision,allocatable :: XmY(:,:)
double precision,allocatable :: A_sta(:,:)
double precision,allocatable :: B_sta(:,:)
double precision,allocatable :: KA_sta(:,:)
double precision,allocatable :: KB_sta(:,:)
! Output variables
double precision,intent(out) :: EcBSE
! Memory allocation
allocate(OmBSE(nS),XpY(nS,nS),XmY(nS,nS),A_sta(nS,nS),KA_sta(nS,nS))
allocate(B_sta(nS,nS),KB_sta(nS,nS))
EcBSE = 0d0
call phGLR_A(dRPA,nBas,nC,nO,nV,nR,nS,1d0,eGF,ERI,A_sta)
if(.not.TDA) call phGLR_B(dRPA,nBas,nC,nO,nV,nR,nS,1d0,ERI,B_sta)
! Compute static kernel
call GGF2_phBSE_static_kernel_A(eta,nBas,nC,nO,nV,nR,nS,1d0,ERI,eGF,KA_sta)
if(.not.TDA) call GGF2_phBSE_static_kernel_B(eta,nBas,nC,nO,nV,nR,nS,1d0,ERI,eGF,KB_sta)
A_sta(:,:) = A_sta(:,:) + KA_sta(:,:)
if(.not.TDA) B_sta(:,:) = B_sta(:,:) + KB_sta(:,:)
! Compute phBSE@GF2 excitation energies
call phGLR(TDA,nS,A_sta,B_sta,EcBSE,OmBSE,XpY,XmY)
call print_excitation_energies('phBSE@GGF2','generalized',nS,OmBSE)
call phLR_transition_vectors(.true.,nBas,nC,nO,nV,nR,nS,dipole_int,OmBSE,XpY,XmY)
! Compute dynamic correction for BSE via perturbation theory
! if(dBSE) &
! call GGF2_phBSE_dynamic_perturbation(dTDA,eta,nBas,nC,nO,nV,nR,nS,ERI,dipole_int,eGF,KA_sta,KB_sta,OmBSE,XpY,XmY)
end subroutine