mirror of
https://github.com/pfloos/quack
synced 2024-06-01 19:05:27 +02:00
59 lines
1.5 KiB
Fortran
59 lines
1.5 KiB
Fortran
subroutine huckel_guess(nBas,nO,S,Hc,ERI,J,K,X,cp,F,Fp,e,c,P)
|
|
|
|
! Hickel guess of the molecular orbitals for HF calculation
|
|
|
|
implicit none
|
|
|
|
! Input variables
|
|
|
|
integer,intent(in) :: nBas
|
|
integer,intent(in) :: nO
|
|
double precision,intent(in) :: S(nBas,nBas)
|
|
double precision,intent(in) :: Hc(nBas,nBas)
|
|
double precision,intent(in) :: ERI(nBas,nBas,nBas,nBas)
|
|
double precision,intent(inout):: J(nBas,nBas)
|
|
double precision,intent(inout):: K(nBas,nBas)
|
|
double precision,intent(in) :: X(nBas,nBas)
|
|
double precision,intent(inout):: cp(nBas,nBas)
|
|
double precision,intent(inout):: F(nBas,nBas)
|
|
double precision,intent(inout):: Fp(nBas,nBas)
|
|
double precision,intent(inout):: e(nBas)
|
|
double precision,intent(inout):: P(nBas,nBas)
|
|
|
|
! Local variables
|
|
|
|
integer :: mu,nu
|
|
double precision :: a
|
|
|
|
! Output variables
|
|
|
|
double precision,intent(out) :: c(nBas,nBas)
|
|
|
|
a = 1.75d0
|
|
|
|
Fp(:,:) = matmul(transpose(X(:,:)),matmul(Hc(:,:),X(:,:)))
|
|
cp(:,:) = Fp(:,:)
|
|
call diagonalize_matrix(nBas,cp,e)
|
|
c(:,:) = matmul(X(:,:),cp(:,:))
|
|
|
|
call Coulomb_matrix_AO_basis(nBas,P,ERI,J)
|
|
call exchange_matrix_AO_basis(nBas,P,ERI,K)
|
|
|
|
F(:,:) = Hc(:,:) + J(:,:) + 0.5d0*K(:,:)
|
|
|
|
do mu=1,nBas
|
|
do nu=mu+1,nBas
|
|
|
|
F(mu,nu) = 0.5d0*a*S(mu,nu)*(Hc(mu,mu) + Hc(nu,nu))
|
|
F(nu,mu) = F(mu,nu)
|
|
|
|
enddo
|
|
enddo
|
|
|
|
Fp(:,:) = matmul(transpose(X(:,:)),matmul(F(:,:),X(:,:)))
|
|
cp(:,:) = Fp(:,:)
|
|
call diagonalize_matrix(nBas,cp,e)
|
|
c(:,:) = matmul(X(:,:),cp(:,:))
|
|
|
|
end subroutine
|