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quack/src/eDFT/lda_correlation_derivative_discontinuity.f90

55 lines
1.3 KiB
Fortran

subroutine lda_correlation_derivative_discontinuity(DFA,nEns,wEns,nGrid,weight,rhow,Ec)
! Compute the correlation LDA part of the derivative discontinuity
implicit none
include 'parameters.h'
! Input variables
character(len=12),intent(in) :: DFA
integer,intent(in) :: nEns
double precision,intent(in) :: wEns(nEns)
integer,intent(in) :: nGrid
double precision,intent(in) :: weight(nGrid)
double precision,intent(in) :: rhow(nGrid,nspin)
! Local variables
double precision :: aC
! Output variables
double precision,intent(out) :: Ec(nsp,nEns)
! Select correlation functional
select case (DFA)
! Wigner's LDA correlation functional: Wigner, Trans. Faraday Soc. 34 (1938) 678
case ('W38')
Ec(:,:) = 0d0
! Vosko, Wilk and Nusair's functional V: Can. J. Phys. 58 (1980) 1200
case ('VWN5')
Ec(:,:) = 0d0
! Loos-Fromager weight-dependent correlation functional: Loos and Fromager (in preparation)
case ('MFL20')
call MFL20_lda_correlation_derivative_discontinuity(nEns,wEns,nGrid,weight(:),rhow(:,:),Ec(:,:))
case default
call print_warning('!!! LDA correlation functional not available !!!')
stop
end select
end subroutine lda_correlation_derivative_discontinuity