quantum-espresso/LR_Modules/setup_dmuxc.f90

87 lines
2.4 KiB
Fortran

!
! Copyright (C) 2001-2016 Quantum ESPRESSO 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 .
!
!-----------------------------------------------------------------------
SUBROUTINE setup_dmuxc
!-----------------------------------------------------------------------
!! This subroutine computes dmuxc (derivative of the XC potential - LDA case).
!
USE kinds, ONLY : DP
USE eqv, ONLY : dmuxc
USE lsda_mod, ONLY : lsda
USE fft_base, ONLY : dfftp
USE scf, ONLY : rho, rho_core
USE noncollin_module, ONLY : noncolin, domag
USE xc_lib, ONLY : dmxc
!
IMPLICIT NONE
!
REAL(DP), ALLOCATABLE :: rho_aux(:,:)
! auxiliary array for density
INTEGER :: ir, is, js, ns, dfftp_nnr
!
CALL start_clock ('setup_dmuxc')
!
dfftp_nnr = dfftp%nnr !to avoid unnecessary copies in acc loop
!
!$acc data copyin( rho ) copyout( dmuxc )
!$acc data copyin( rho%of_r )
!
ns = 1
IF ( lsda ) ns = 2
IF ( (.NOT. lsda) .AND. noncolin .AND. domag ) ns = 4
!
ALLOCATE( rho_aux(dfftp%nnr,ns) )
!$acc data create( rho_aux )
!
IF ( lsda ) THEN
!
!$acc parallel loop present(rho) copyin(rho_core)
DO ir = 1, dfftp_nnr
rho_aux(ir,1) = ( rho%of_r(ir,1) + rho%of_r(ir,2) + rho_core(ir) )*0.5_DP
rho_aux(ir,2) = ( rho%of_r(ir,1) - rho%of_r(ir,2) + rho_core(ir) )*0.5_DP
ENDDO
!
CALL dmxc( dfftp_nnr, 2, rho_aux, dmuxc, gpu_args_=.TRUE. )
!
ELSE
!
IF ( noncolin .AND. domag ) THEN
!
!$acc parallel loop present(rho) copyin(rho_core)
DO ir = 1, dfftp_nnr
rho_aux(ir,1) = rho%of_r(ir,1) + rho_core(ir)
rho_aux(ir,2:4) = rho%of_r(ir,2:4)
ENDDO
!
CALL dmxc( dfftp_nnr, 4, rho_aux, dmuxc, gpu_args_=.TRUE. )
!
ELSE
!
!$acc parallel loop present(rho) copyin(rho_core)
DO ir = 1, dfftp_nnr
rho_aux(ir,1) = rho%of_r(ir,1) + rho_core(ir)
ENDDO
!
CALL dmxc( dfftp_nnr, 1, rho_aux, dmuxc, gpu_args_=.TRUE. )
!
ENDIF
!
ENDIF
!
!$acc end data
DEALLOCATE( rho_aux )
!
!$acc end data
!$acc end data
!
CALL stop_clock ('setup_dmuxc')
!
RETURN
!
END SUBROUTINE setup_dmuxc