mirror of
https://github.com/pfloos/quack
synced 2024-09-01 17:13:45 +02:00
144 lines
4.8 KiB
Fortran
144 lines
4.8 KiB
Fortran
subroutine Bethe_Salpeter(TDA_W,TDA,dBSE,dTDA,evDyn,singlet,triplet,eta,nBas,nC,nO,nV,nR,nS,ERI,dipole_int,eW,eGW,EcBSE)
|
|
|
|
! Compute the Bethe-Salpeter excitation energies
|
|
|
|
implicit none
|
|
include 'parameters.h'
|
|
|
|
! Input variables
|
|
|
|
logical,intent(in) :: TDA_W
|
|
logical,intent(in) :: TDA
|
|
logical,intent(in) :: dBSE
|
|
logical,intent(in) :: dTDA
|
|
logical,intent(in) :: evDyn
|
|
logical,intent(in) :: singlet
|
|
logical,intent(in) :: triplet
|
|
|
|
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) :: eW(nBas)
|
|
double precision,intent(in) :: eGW(nBas)
|
|
double precision,intent(in) :: ERI(nBas,nBas,nBas,nBas)
|
|
double precision,intent(in) :: dipole_int(nBas,nBas,ncart)
|
|
|
|
! Local variables
|
|
|
|
integer :: ispin
|
|
integer :: isp_W
|
|
|
|
double precision :: EcRPA
|
|
double precision,allocatable :: OmRPA(:)
|
|
double precision,allocatable :: XpY_RPA(:,:)
|
|
double precision,allocatable :: XmY_RPA(:,:)
|
|
double precision,allocatable :: rho_RPA(:,:,:)
|
|
|
|
double precision,allocatable :: OmBSE(:,:)
|
|
double precision,allocatable :: XpY_BSE(:,:,:)
|
|
double precision,allocatable :: XmY_BSE(:,:,:)
|
|
|
|
! Output variables
|
|
|
|
double precision,intent(out) :: EcBSE(nspin)
|
|
|
|
! Memory allocation
|
|
|
|
allocate(OmRPA(nS),XpY_RPA(nS,nS),XmY_RPA(nS,nS),rho_RPA(nBas,nBas,nS))
|
|
allocate(OmBSE(nS,nspin),XpY_BSE(nS,nS,nspin),XmY_BSE(nS,nS,nspin))
|
|
|
|
!---------------------------------
|
|
! Compute (singlet) RPA screening
|
|
!---------------------------------
|
|
|
|
isp_W = 1
|
|
EcRPA = 0d0
|
|
|
|
call linear_response(isp_W,.true.,TDA_W,.false.,eta,nBas,nC,nO,nV,nR,nS,1d0,eW,ERI,OmRPA, &
|
|
rho_RPA,EcRPA,OmRPA,XpY_RPA,XmY_RPA)
|
|
call excitation_density(nBas,nC,nO,nR,nS,ERI,XpY_RPA,rho_RPA)
|
|
|
|
!-------------------
|
|
! Singlet manifold
|
|
!-------------------
|
|
|
|
if(singlet) then
|
|
|
|
ispin = 1
|
|
EcBSE(ispin) = 0d0
|
|
|
|
! Compute BSE excitation energies
|
|
|
|
call linear_response(ispin,.true.,TDA,.true.,eta,nBas,nC,nO,nV,nR,nS,1d0,eGW,ERI,OmRPA, &
|
|
rho_RPA,EcBSE(ispin),OmBSE(:,ispin),XpY_BSE(:,:,ispin),XmY_BSE(:,:,ispin))
|
|
call print_excitation('BSE@GW ',ispin,nS,OmBSE(:,ispin))
|
|
call print_transition_vectors(.true.,nBas,nC,nO,nV,nR,nS,dipole_int, &
|
|
OmBSE(:,ispin),XpY_BSE(:,:,ispin),XmY_BSE(:,:,ispin))
|
|
|
|
!-------------------------------------------------
|
|
! Compute the dynamical screening at the BSE level
|
|
!-------------------------------------------------
|
|
|
|
if(dBSE) then
|
|
|
|
! Compute dynamic correction for BSE via perturbation theory (iterative or renormalized)
|
|
|
|
if(evDyn) then
|
|
|
|
call Bethe_Salpeter_dynamic_perturbation_iterative(dTDA,eta,nBas,nC,nO,nV,nR,nS,eGW,dipole_int,OmRPA,rho_RPA, &
|
|
OmBSE(:,ispin),XpY_BSE(:,:,ispin),XmY_BSE(:,:,ispin))
|
|
else
|
|
|
|
call Bethe_Salpeter_dynamic_perturbation(dTDA,eta,nBas,nC,nO,nV,nR,nS,eW,eGW,dipole_int,OmRPA,rho_RPA, &
|
|
OmBSE(:,ispin),XpY_BSE(:,:,ispin),XmY_BSE(:,:,ispin))
|
|
end if
|
|
|
|
end if
|
|
|
|
end if
|
|
|
|
!-------------------
|
|
! Triplet manifold
|
|
!-------------------
|
|
|
|
if(triplet) then
|
|
|
|
ispin = 2
|
|
EcBSE(ispin) = 0d0
|
|
|
|
! Compute BSE excitation energies
|
|
|
|
call linear_response(ispin,.true.,TDA,.true.,eta,nBas,nC,nO,nV,nR,nS,1d0,eGW,ERI,OmRPA, &
|
|
rho_RPA,EcBSE(ispin),OmBSE(:,ispin),XpY_BSE(:,:,ispin),XmY_BSE(:,:,ispin))
|
|
call print_excitation('BSE@GW ',ispin,nS,OmBSE(:,ispin))
|
|
call print_transition_vectors(.false.,nBas,nC,nO,nV,nR,nS,dipole_int, &
|
|
OmBSE(:,ispin),XpY_BSE(:,:,ispin),XmY_BSE(:,:,ispin))
|
|
|
|
!-------------------------------------------------
|
|
! Compute the dynamical screening at the BSE level
|
|
!-------------------------------------------------
|
|
|
|
if(dBSE) then
|
|
|
|
! Compute dynamic correction for BSE via perturbation theory (iterative or renormalized)
|
|
|
|
if(evDyn) then
|
|
|
|
call Bethe_Salpeter_dynamic_perturbation_iterative(dTDA,eta,nBas,nC,nO,nV,nR,nS,eGW,dipole_int,OmRPA,rho_RPA, &
|
|
OmBSE(:,ispin),XpY_BSE(:,:,ispin),XmY_BSE(:,:,ispin))
|
|
else
|
|
|
|
call Bethe_Salpeter_dynamic_perturbation(dTDA,eta,nBas,nC,nO,nV,nR,nS,eW,eGW,dipole_int,OmRPA,rho_RPA, &
|
|
OmBSE(:,ispin),XpY_BSE(:,:,ispin),XmY_BSE(:,:,ispin))
|
|
end if
|
|
|
|
end if
|
|
|
|
end if
|
|
|
|
end subroutine Bethe_Salpeter
|