mirror of
https://github.com/pfloos/quack
synced 2024-09-02 01:23:44 +02:00
215 lines
4.8 KiB
Fortran
215 lines
4.8 KiB
Fortran
subroutine ufBSE(nBas,nC,nO,nV,nR,nS,ENuc,ERHF,ERI,eHF,eGW)
|
|
|
|
! Unfold BSE@GW equations
|
|
|
|
implicit none
|
|
include 'parameters.h'
|
|
|
|
! Input variables
|
|
|
|
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) :: ENuc
|
|
double precision,intent(in) :: ERHF
|
|
double precision,intent(in) :: ERI(nBas,nBas,nBas,nBas)
|
|
double precision,intent(in) :: eHF(nBas)
|
|
double precision,intent(in) :: eGW(nBas)
|
|
|
|
! Local variables
|
|
|
|
integer :: s
|
|
integer :: i,j,k,l
|
|
integer :: a,b,c,d
|
|
integer :: ia,jb,kc,iajb,kcld
|
|
double precision :: tmp
|
|
|
|
integer :: n1h1p,n2h2p,nH
|
|
double precision,external :: Kronecker_delta
|
|
|
|
integer,allocatable :: order(:)
|
|
double precision,allocatable :: H(:,:)
|
|
double precision,allocatable :: X(:,:)
|
|
double precision,allocatable :: Om(:)
|
|
double precision,allocatable :: Z(:)
|
|
|
|
! Output variables
|
|
|
|
! Hello world
|
|
|
|
write(*,*)
|
|
write(*,*)'**********************************************'
|
|
write(*,*)'| Unfolded BSE@GW calculation |'
|
|
write(*,*)'**********************************************'
|
|
write(*,*)
|
|
|
|
! TDA for W
|
|
|
|
write(*,*) 'Tamm-Dancoff approximation by default!'
|
|
write(*,*)
|
|
|
|
! Dimension of the supermatrix
|
|
|
|
n1h1p = nO*nV
|
|
n2h2p = nO*nO*nV*nV
|
|
nH = n1h1p + n2h2p + n2h2p
|
|
|
|
! Memory allocation
|
|
|
|
allocate(order(nH),H(nH,nH),X(nH,nH),Om(nH),Z(nH))
|
|
|
|
! Initialization
|
|
|
|
H(:,:) = 0d0
|
|
|
|
!---------------------------!
|
|
! Compute GW supermatrix !
|
|
!---------------------------!
|
|
! !
|
|
! | A -Ve -Vh | !
|
|
! | | !
|
|
! H = | +Vh C2h2p 0 | !
|
|
! | | !
|
|
! | +Ve 0 C2p2h | !
|
|
! !
|
|
!---------------------------!
|
|
|
|
!---------!
|
|
! Block A !
|
|
!---------!
|
|
|
|
ia = 0
|
|
do i=nC+1,nO
|
|
do a=nO+1,nBas-nR
|
|
ia = ia + 1
|
|
|
|
jb = 0
|
|
do j=nC+1,nO
|
|
do b=nO+1,nBas-nR
|
|
jb = jb + 1
|
|
|
|
H(ia,jb) = (eGW(a) - eGW(i))*Kronecker_delta(i,j)*Kronecker_delta(a,b) &
|
|
+ 2d0*ERI(i,b,a,j) - ERI(i,b,j,a)
|
|
|
|
end do
|
|
end do
|
|
|
|
end do
|
|
end do
|
|
|
|
!----------------!
|
|
! Blocks Vp & Ve !
|
|
!----------------!
|
|
|
|
iajb=0
|
|
do i=nC+1,nO
|
|
do a=nO+1,nBas-nR
|
|
do j=nC+1,nO
|
|
do b=nO+1,nBas-nR
|
|
iajb = iajb + 1
|
|
|
|
kc = 0
|
|
do k=nC+1,nO
|
|
do c=nO+1,nBas-nR
|
|
kc = kc + 1
|
|
|
|
tmp = sqrt(2d0)*Kronecker_delta(k,j)*ERI(b,a,c,i)
|
|
H(n1h1p+iajb,kc ) = +tmp
|
|
H(kc ,n1h1p+n2h2p+iajb) = -tmp
|
|
|
|
tmp = sqrt(2d0)*Kronecker_delta(b,c)*ERI(a,k,i,j)
|
|
H(n1h1p+n2h2p+iajb,kc ) = +tmp
|
|
H(kc ,n1h1p+iajb) = -tmp
|
|
|
|
end do
|
|
end do
|
|
|
|
end do
|
|
end do
|
|
end do
|
|
end do
|
|
|
|
!-------------!
|
|
! Block 2h2p !
|
|
!-------------!
|
|
|
|
iajb = 0
|
|
do i=nC+1,nO
|
|
do a=nO+1,nBas-nR
|
|
do j=nC+1,nO
|
|
do b=nO+1,nBas-nR
|
|
iajb = iajb + 1
|
|
|
|
kcld = 0
|
|
do k=nC+1,nO
|
|
do c=nO+1,nBas-nR
|
|
do l=nC+1,nO
|
|
do d=nO+1,nBas-nR
|
|
kcld = kcld + 1
|
|
|
|
tmp = ((eHF(a) + eGW(b) - eHF(i) - eGW(j))*Kronecker_delta(i,k)*Kronecker_delta(a,c) &
|
|
+ 2d0*ERI(a,k,i,c))*Kronecker_delta(j,l)*Kronecker_delta(b,d)
|
|
H(n1h1p +iajb,n1h1p +kcld) = tmp
|
|
H(n1h1p+n2h2p+iajb,n1h1p+n2h2p+kcld) = tmp
|
|
|
|
end do
|
|
end do
|
|
end do
|
|
end do
|
|
|
|
end do
|
|
end do
|
|
end do
|
|
end do
|
|
|
|
!-------------------------!
|
|
! Diagonalize supermatrix !
|
|
!-------------------------!
|
|
|
|
! call matout(nH,nH,H)
|
|
|
|
call diagonalize_general_matrix(nH,H,Om,X)
|
|
|
|
do s=1,nH
|
|
order(s) = s
|
|
end do
|
|
|
|
call quick_sort(Om,order,nH)
|
|
call set_order(X,order,nH,nH)
|
|
|
|
!-----------------!
|
|
! Compute weights !
|
|
!-----------------!
|
|
|
|
Z(:) = 0d0
|
|
do s=1,nH
|
|
do ia=1,n1h1p
|
|
Z(s) = Z(s) + X(ia,s)**2
|
|
end do
|
|
end do
|
|
|
|
!--------------!
|
|
! Dump results !
|
|
!--------------!
|
|
|
|
write(*,*)'-------------------------------------------'
|
|
write(*,*)' unfolded BSE excitation energies (eV) '
|
|
write(*,*)'-------------------------------------------'
|
|
write(*,'(1X,A1,1X,A3,1X,A1,1X,A15,1X,A1,1X,A15,1X,A1,1X,A15,1X)') &
|
|
'|','#','|','Omega (eV)','|','Z','|'
|
|
write(*,*)'-------------------------------------------'
|
|
|
|
do s=1,nH
|
|
if(Z(s) > 1d-7) &
|
|
write(*,'(1X,A1,1X,I3,1X,A1,1X,F15.6,1X,A1,1X,F15.6,1X,A1,1X)') &
|
|
'|',s,'|',Om(s)*HaToeV,'|',Z(s),'|'
|
|
enddo
|
|
|
|
write(*,*)'-------------------------------------------'
|
|
write(*,*)
|
|
|
|
end subroutine ufBSE
|