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39 lines
840 B
Fortran
39 lines
840 B
Fortran
subroutine lda_exchange_energy(DFA,nEns,wEns,nGrid,weight,rho,Ex)
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! Select LDA exchange functional
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implicit none
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include 'parameters.h'
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! Input variables
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character(len=12),intent(in) :: DFA
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integer,intent(in) :: nEns
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double precision,intent(in) :: wEns(nEns)
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integer,intent(in) :: nGrid
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double precision,intent(in) :: weight(nGrid)
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double precision,intent(in) :: rho(nGrid)
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! Output variables
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double precision,intent(out) :: Ex
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! Select correlation functional
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select case (DFA)
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! Slater's LDA correlation functional: Slater, Phys. Rev. 81 (1951) 385
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case ('S51')
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call S51_lda_exchange_energy(nGrid,weight,rho,Ex)
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case default
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call print_warning('!!! LDA exchange functional not available !!!')
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stop
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end select
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end subroutine lda_exchange_energy
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