mirror of https://github.com/pfloos/quack
31 lines
536 B
Fortran
31 lines
536 B
Fortran
subroutine density_matrix(nBas,ON,c,P)
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! Compute density matrix based on the occupation numbers
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implicit none
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! Input variables
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integer,intent(in) :: nBas
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double precision,intent(in) :: ON(nBas),c(nBas,nBas)
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! Local variables
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integer :: mu,nu,i
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! Output variables
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double precision,intent(out) :: P(nBas,nBas)
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P(:,:) = 0d0
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do i=1,nBas
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do nu=1,nBas
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do mu=1,nBas
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P(mu,nu) = P(mu,nu) + 2d0*ON(i)*c(mu,i)*c(nu,i)
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end do
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end do
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end do
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end subroutine
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