quack/src/RPA/ACFDT.f90

172 lines
5.3 KiB
Fortran

subroutine ACFDT(exchange_kernel,doXBS,dRPA,TDA_W,TDA,BSE,singlet,triplet,eta,nBas,nC,nO,nV,nR,nS,ERI,eW,e,EcAC)
! Compute the correlation energy via the adiabatic connection fluctuation dissipation theorem
implicit none
include 'parameters.h'
include 'quadrature.h'
! Input variables
logical,intent(in) :: doXBS
logical,intent(in) :: exchange_kernel
logical,intent(in) :: dRPA
logical,intent(in) :: TDA_W
logical,intent(in) :: TDA
logical,intent(in) :: BSE
logical,intent(in) :: singlet
logical,intent(in) :: triplet
double precision,intent(in) :: eta
integer,intent(in) :: nBas,nC,nO,nV,nR,nS
double precision,intent(in) :: eW(nBas)
double precision,intent(in) :: e(nBas)
double precision,intent(in) :: ERI(nBas,nBas,nBas,nBas)
! Local variables
integer :: ispin
integer :: isp_W
integer :: iAC
double precision :: lambda
double precision,allocatable :: Ec(:,:)
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 :: Omega(:,:)
double precision,allocatable :: XpY(:,:,:)
double precision,allocatable :: XmY(:,:,:)
! Output variables
double precision,intent(out) :: EcAC(nspin)
! Memory allocation
allocate(Ec(nAC,nspin))
allocate(OmRPA(nS),XpY_RPA(nS,nS),XmY_RPA(nS,nS),rho_RPA(nBas,nBas,nS))
allocate(Omega(nS,nspin),XpY(nS,nS,nspin),XmY(nS,nS,nspin))
! Antisymmetrized kernel version
if(exchange_kernel) then
write(*,*)
write(*,*) '*** Exchange kernel version ***'
write(*,*)
end if
EcAC(:) = 0d0
Ec(:,:) = 0d0
! 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
write(*,*) '--------------'
write(*,*) 'Singlet states'
write(*,*) '--------------'
write(*,*)
write(*,*) '-----------------------------------------------------------------------------------'
write(*,'(2X,A15,1X,A30,1X,A30)') 'lambda','Ec(lambda)','Tr(K x P_lambda)'
write(*,*) '-----------------------------------------------------------------------------------'
do iAC=1,nAC
lambda = rAC(iAC)
if(doXBS) then
call linear_response(isp_W,.true.,TDA_W,.false.,eta,nBas,nC,nO,nV,nR,nS,lambda,eW,ERI,OmRPA, &
rho_RPA,EcRPA,OmRPA,XpY_RPA,XmY_RPA)
call excitation_density(nBas,nC,nO,nR,nS,ERI,XpY_RPA,rho_RPA)
end if
call linear_response(ispin,dRPA,TDA,BSE,eta,nBas,nC,nO,nV,nR,nS,lambda,e,ERI,OmRPA, &
rho_RPA,EcAC(ispin),Omega(:,ispin),XpY(:,:,ispin),XmY(:,:,ispin))
call ACFDT_correlation_energy(ispin,exchange_kernel,nBas,nC,nO,nV,nR,nS, &
ERI,XpY(:,:,ispin),XmY(:,:,ispin),Ec(iAC,ispin))
write(*,'(2X,F15.6,1X,F30.15,1X,F30.15)') lambda,EcAC(ispin),Ec(iAC,ispin)
end do
EcAC(ispin) = 0.5d0*dot_product(wAC,Ec(:,ispin))
if(exchange_kernel) EcAC(ispin) = 0.5d0*EcAC(ispin)
write(*,*) '-----------------------------------------------------------------------------------'
write(*,'(2X,A50,1X,F15.6)') ' Ec(AC) via Gauss-Legendre quadrature:',EcAC(ispin)
write(*,*) '-----------------------------------------------------------------------------------'
write(*,*)
end if
! Triplet manifold
if(triplet) then
ispin = 2
write(*,*) '--------------'
write(*,*) 'Triplet states'
write(*,*) '--------------'
write(*,*)
write(*,*) '-----------------------------------------------------------------------------------'
write(*,'(2X,A15,1X,A30,1X,A30)') 'lambda','Ec(lambda)','Tr(K x P_lambda)'
write(*,*) '-----------------------------------------------------------------------------------'
do iAC=1,nAC
lambda = rAC(iAC)
if(doXBS) then
call linear_response(isp_W,.true.,TDA_W,.false.,eta,nBas,nC,nO,nV,nR,nS,lambda,eW,ERI,OmRPA, &
rho_RPA,EcRPA,OmRPA,XpY_RPA,XmY_RPA)
call excitation_density(nBas,nC,nO,nR,nS,ERI,XpY_RPA,rho_RPA)
end if
call linear_response(ispin,dRPA,TDA,BSE,eta,nBas,nC,nO,nV,nR,nS,lambda,e,ERI,OmRPA, &
rho_RPA,EcAC(ispin),Omega(:,ispin),XpY(:,:,ispin),XmY(:,:,ispin))
call ACFDT_correlation_energy(ispin,exchange_kernel,nBas,nC,nO,nV,nR,nS,ERI,XpY(:,:,ispin),XmY(:,:,ispin),Ec(iAC,ispin))
write(*,'(2X,F15.6,1X,F30.15,1X,F30.15)') lambda,EcAC(ispin),Ec(iAC,ispin)
end do
EcAC(ispin) = 0.5d0*dot_product(wAC,Ec(:,ispin))
if(exchange_kernel) EcAC(ispin) = 1.5d0*EcAC(ispin)
write(*,*) '-----------------------------------------------------------------------------------'
write(*,'(2X,A50,1X,F15.6)') ' Ec(AC) via Gauss-Legendre quadrature:',EcAC(ispin)
write(*,*) '-----------------------------------------------------------------------------------'
write(*,*)
end if
end subroutine ACFDT