2003-01-20 05:58:50 +08:00
|
|
|
!
|
2003-01-28 20:28:11 +08:00
|
|
|
! Copyright (C) 2003 PWSCF group
|
|
|
|
! This file is distributed under the terms of the
|
|
|
|
! GNU General Public License. See the file `License'
|
|
|
|
! in the root directory of the present distribution,
|
|
|
|
! or http://www.gnu.org/copyleft/gpl.txt .
|
|
|
|
!
|
|
|
|
!
|
2003-01-20 05:58:50 +08:00
|
|
|
!-----------------------------------------------------------------------
|
|
|
|
subroutine A_h(e,h,ah)
|
|
|
|
!-----------------------------------------------------------------------
|
|
|
|
#include "machine.h"
|
|
|
|
use parameters, only: DP
|
|
|
|
use pwcom
|
2003-10-03 22:01:11 +08:00
|
|
|
USE wavefunctions, ONLY: evc, psic
|
|
|
|
USE constants, ONLY: degspin
|
2003-01-20 05:58:50 +08:00
|
|
|
use gamma
|
|
|
|
use rbecmod
|
|
|
|
use cgcom
|
|
|
|
use funct
|
|
|
|
!
|
|
|
|
implicit none
|
|
|
|
integer :: j, jkb, ibnd, na,nt,ih
|
|
|
|
real(kind=DP) :: e(nbnd)
|
|
|
|
complex(kind=DP) :: h(npwx,nbnd), ah(npwx,nbnd)
|
|
|
|
!
|
|
|
|
complex(kind=DP) :: fp, fm
|
2003-02-08 00:04:36 +08:00
|
|
|
complex(kind=DP), pointer :: dpsic(:), drhoc(:), dvxc(:)
|
|
|
|
real(kind=DP), pointer :: dv(:), drho(:)
|
2003-01-20 05:58:50 +08:00
|
|
|
!
|
|
|
|
call start_clock('a_h')
|
|
|
|
!
|
|
|
|
drho => auxr
|
|
|
|
dpsic => aux2
|
|
|
|
drhoc => aux3
|
|
|
|
!
|
2003-09-18 05:50:03 +08:00
|
|
|
drho(:) = 0.d0
|
2003-01-20 05:58:50 +08:00
|
|
|
!
|
|
|
|
! [(k+G)^2 - e ]psi
|
|
|
|
do ibnd = 1,nbnd
|
2003-02-08 00:04:36 +08:00
|
|
|
! set to zero the imaginary part of h at G=0
|
2003-01-20 05:58:50 +08:00
|
|
|
! needed for numerical stability
|
|
|
|
if (gstart==2) h(1,ibnd) = cmplx(DREAL(h(1,ibnd)),0.d0)
|
|
|
|
do j = 1,npw
|
|
|
|
ah(j,ibnd) = (g2kin(j)-e(ibnd)) * h(j,ibnd)
|
|
|
|
end do
|
|
|
|
end do
|
|
|
|
! V_Loc psi
|
|
|
|
do ibnd = 1,nbnd, 2
|
2003-09-18 05:50:03 +08:00
|
|
|
dpsic(:)= (0.d0, 0.d0)
|
|
|
|
psic(:) = (0.d0, 0.d0)
|
2003-01-20 05:58:50 +08:00
|
|
|
if (ibnd.lt.nbnd) then
|
|
|
|
! two ffts at the same time
|
|
|
|
do j = 1,npw
|
|
|
|
psic (nl (igk(j))) = evc(j,ibnd) + (0.0,1.d0)* evc(j,ibnd+1)
|
|
|
|
dpsic(nl (igk(j))) = h(j,ibnd) + (0.0,1.d0)* h(j,ibnd+1)
|
|
|
|
psic (nlm(igk(j)))= conjg(evc(j,ibnd)-(0.0,1.d0)* evc(j,ibnd+1))
|
|
|
|
dpsic(nlm(igk(j)))= conjg( h(j,ibnd)-(0.0,1.d0)* h(j,ibnd+1))
|
|
|
|
end do
|
|
|
|
else
|
|
|
|
do j = 1,npw
|
|
|
|
psic (nl (igk(j))) = evc(j,ibnd)
|
|
|
|
dpsic(nl (igk(j))) = h(j,ibnd)
|
|
|
|
psic (nlm(igk(j))) = conjg( evc(j,ibnd))
|
|
|
|
dpsic(nlm(igk(j))) = conjg( h(j,ibnd))
|
|
|
|
end do
|
|
|
|
end if
|
|
|
|
call cft3s( psic,nr1,nr2,nr3,nrx1,nr2,nr3,2)
|
|
|
|
call cft3s(dpsic,nr1,nr2,nr3,nrx1,nr2,nr3,2)
|
|
|
|
do j = 1,nrxx
|
|
|
|
drho(j) = drho(j) - 2.0*degspin/omega * &
|
|
|
|
DREAL(psic(j)*conjg(dpsic(j)))
|
|
|
|
dpsic(j) = dpsic(j) * vrs(j,current_spin)
|
|
|
|
end do
|
|
|
|
call cft3s(dpsic,nr1,nr2,nr3,nrx1,nr2,nr3,-2)
|
|
|
|
if (ibnd.lt.nbnd) then
|
|
|
|
! two ffts at the same time
|
|
|
|
do j = 1,npw
|
|
|
|
fp = (dpsic (nl(igk(j))) + dpsic (nlm(igk(j))))*0.5d0
|
|
|
|
fm = (dpsic (nl(igk(j))) - dpsic (nlm(igk(j))))*0.5d0
|
|
|
|
ah(j,ibnd ) = ah(j,ibnd) +cmplx(DREAL(fp), DIMAG(fm))
|
|
|
|
ah(j,ibnd+1) = ah(j,ibnd+1)+cmplx(DIMAG(fp),-DREAL(fm))
|
|
|
|
end do
|
|
|
|
else
|
|
|
|
do j = 1,npw
|
|
|
|
ah(j,ibnd) = ah(j,ibnd) + dpsic (nl(igk(j)))
|
|
|
|
end do
|
|
|
|
end if
|
|
|
|
end do
|
|
|
|
!
|
|
|
|
nullify(dpsic)
|
|
|
|
! V_NL psi
|
|
|
|
call pw_gemm ('Y', nkb, nbnd, npw, vkb, npwx, h, npwx, becp, nkb)
|
|
|
|
if (nkb.gt.0) call add_vuspsi (npwx, npw, nbnd, h, ah)
|
|
|
|
!
|
|
|
|
do j = 1,nrxx
|
|
|
|
drhoc(j) = DCMPLX(drho(j),0.d0)
|
|
|
|
end do
|
|
|
|
call cft3(drhoc,nr1,nr2,nr3,nrx1,nr2,nr3,-1)
|
|
|
|
!
|
2003-02-08 00:04:36 +08:00
|
|
|
! drho is deltarho(r), drhoc is deltarho(g)
|
2003-01-20 05:58:50 +08:00
|
|
|
!
|
|
|
|
! mu'(n(r)) psi(r) delta psi(r)
|
|
|
|
!
|
|
|
|
dvxc => aux2
|
|
|
|
do j = 1,nrxx
|
|
|
|
dvxc(j) = drho(j)*dmuxc(j)
|
|
|
|
end do
|
|
|
|
!
|
2003-02-08 00:04:36 +08:00
|
|
|
! add gradient correction contribution (if any)
|
2003-01-20 05:58:50 +08:00
|
|
|
!
|
|
|
|
call start_clock('dgradcorr')
|
|
|
|
if (igcx.ne.0.or.igcc.ne.0) call dgradcor1 &
|
|
|
|
(rho, grho, dvxc_rr, dvxc_sr, dvxc_ss, dvxc_s, &
|
|
|
|
drho, drhoc, nr1,nr2,nr3, nrx1, nrx2, nrx3, nrxx, nspin, &
|
|
|
|
nl, nlm, ngm, g, alat, omega, dvxc)
|
|
|
|
call stop_clock('dgradcorr')
|
|
|
|
nullify (drho)
|
|
|
|
!
|
|
|
|
! 1/|r-r'| * psi(r') delta psi(r')
|
|
|
|
!
|
|
|
|
! gstart is the first nonzero G vector (needed for parallel execution)
|
|
|
|
!
|
|
|
|
if (gstart==2) drhoc(nl(1)) = 0.d0
|
|
|
|
!
|
|
|
|
do j = gstart,ngm
|
|
|
|
drhoc(nl (j)) = e2*fpi*drhoc(nl(j))/ (tpiba2*gg(j))
|
|
|
|
drhoc(nlm(j)) = conjg(drhoc(nl (j)))
|
|
|
|
end do
|
|
|
|
call cft3(drhoc,nr1,nr2,nr3,nrx1,nr2,nr3,+1)
|
|
|
|
!
|
|
|
|
! drhoc now contains deltaV_hartree
|
|
|
|
!
|
|
|
|
dv => auxr
|
|
|
|
do j = 1,nrxx
|
|
|
|
dv(j) = - DREAL(dvxc(j)) - DREAL(drhoc(j))
|
|
|
|
end do
|
|
|
|
!
|
2003-02-08 00:04:36 +08:00
|
|
|
call vloc_psi(npwx, npw, nbnd, evc, dv, ah)
|
2003-01-20 05:58:50 +08:00
|
|
|
!
|
|
|
|
! set to zero the imaginary part of ah at G=0
|
|
|
|
! needed for numerical stability
|
|
|
|
if (gstart.eq.2) then
|
|
|
|
do ibnd = 1, nbnd
|
|
|
|
ah(1,ibnd) = cmplx(DREAL(ah(1,ibnd)),0.d0)
|
|
|
|
end do
|
|
|
|
end if
|
|
|
|
!
|
|
|
|
call stop_clock('a_h')
|
|
|
|
!
|
|
|
|
return
|
|
|
|
end subroutine A_h
|