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55 lines
1.1 KiB
Fortran
55 lines
1.1 KiB
Fortran
subroutine US51_lda_exchange_energy(nGrid,weight,rho,ExLDA)
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use xc_f90_lib_m
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! Compute Slater's LDA exchange energy
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implicit none
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include 'parameters.h'
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! Input variables
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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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! Local variables
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integer(8) :: nGri8
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integer :: iG
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double precision :: r
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double precision,allocatable :: Ex(:)
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TYPE(xc_f90_func_t) :: xc_func
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TYPE(xc_f90_func_info_t) :: xc_info
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integer :: func_id = 1
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! Output variables
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double precision :: ExLDA
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! Memory allocation
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nGri8 = int(nGrid,8)
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print*,nGri8
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allocate(Ex(nGrid))
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call xc_f90_func_init(xc_func, func_id, XC_POLARIZED)
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xc_info = xc_f90_func_get_info(xc_func)
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call xc_f90_lda_exc(xc_func, nGri8, rho(1), Ex(1))
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ExLDA = 0d0
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! do iG=1,nGrid
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! write(*,"(F8.6,1X,F9.6)") rho(iG), Ex(iG)
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! ExLDA = ExLDA + weight(iG)*Ex(iG)
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! enddo
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call xc_f90_func_end(xc_func)
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end subroutine US51_lda_exchange_energy
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