1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57
|
! Copyright (C) 2009 T. McQueen and J. K. Dewhurst.
! This file is distributed under the terms of the GNU General Public License.
! See the file COPYING for license details.
!BOP
! !ROUTINE: ggair_2a
! !INTERFACE:
subroutine ggair_2a(rho,g2rho,gvrho,grho2)
! !USES:
use modmain
! !DESCRIPTION:
! Spin-unpolarised version of {\tt ggair\_sp\_2a}.
!
! !REVISION HISTORY:
! Created November 2009 (JKD and TMcQ)
!EOP
!BOC
implicit none
! arguments
real(8), intent(in) :: rho(ngtot)
real(8), intent(out) :: g2rho(ngtot),gvrho(ngtot,3),grho2(ngtot)
! local variables
integer ig,ifg,i
! allocatable arrays
complex(8), allocatable :: zfft1(:),zfft2(:)
allocate(zfft1(nfgrz),zfft2(nfgrz))
! Fourier transform density to G-space
call rzfftifc(3,ngridg,-1,rho,zfft1)
! ∇²ρ
do ifg=1,nfgrz
ig=igrzf(ifg)
if (ig <= ngvc) then
zfft2(ifg)=-(gc(ig)**2)*zfft1(ifg)
else
zfft2(ifg)=0.d0
end if
end do
call rzfftifc(3,ngridg,1,g2rho,zfft2)
! ∇ρ
do i=1,3
do ifg=1,nfgrz
ig=igrzf(ifg)
if (ig <= ngvc) then
zfft2(ifg)=vgc(i,ig)*cmplx(-zfft1(ifg)%im,zfft1(ifg)%re,8)
else
zfft2(ifg)=0.d0
end if
end do
call rzfftifc(3,ngridg,1,gvrho(:,i),zfft2)
end do
! (∇ρ)²
grho2(1:ngtot)=gvrho(1:ngtot,1)**2+gvrho(1:ngtot,2)**2+gvrho(1:ngtot,3)**2
deallocate(zfft1,zfft2)
end subroutine
!EOC
|