mirror of https://gitlab.com/QEF/q-e.git
259 lines
9.5 KiB
Fortran
259 lines
9.5 KiB
Fortran
!
|
|
! Copyright (C) 2001-2008 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 dvqpsi_us_only (ik, uact, becp1, alphap)
|
|
!----------------------------------------------------------------------
|
|
!! This routine calculates \(\text{dV_bare}/\text{dtau}\cdot\text{psi}\)
|
|
!! for one perturbation with a given q.
|
|
!! The displacements are described by a vector uact.
|
|
!! The result is stored in \(\text{dvpsi}\). The routine is called for
|
|
!! each k-point and for each pattern u. It computes simultaneously all
|
|
!! the bands.
|
|
!! This routine implements Eq. (B29) of PRB 64, 235118 (2001).
|
|
!! Only the contribution of the nonlocal potential is calculated here.
|
|
!
|
|
!
|
|
USE kinds, only : DP
|
|
USE cell_base, ONLY : tpiba
|
|
USE gvect, ONLY : g
|
|
USE klist, ONLY : xk, ngk, igk_k
|
|
USE ions_base, ONLY : nat, ityp, ntyp => nsp
|
|
USE lsda_mod, ONLY : lsda, current_spin, isk, nspin
|
|
USE wvfct, ONLY : nbnd, npwx, et
|
|
USE noncollin_module, ONLY : noncolin, npol, lspinorb
|
|
USE uspp, ONLY: okvan, nkb, vkb
|
|
USE uspp_param, ONLY: nh, nhm
|
|
USE phus, ONLY : int1, int1_nc, int2, int2_so
|
|
|
|
USE qpoint, ONLY : nksq, ikks, ikqs
|
|
USE becmod, ONLY : bec_type
|
|
USE eqv, ONLY : dvpsi
|
|
USE control_lr, ONLY : lgamma
|
|
|
|
implicit none
|
|
!
|
|
integer :: ik
|
|
!! input: the k point
|
|
complex(DP) :: uact(3*nat)
|
|
!! input: the pattern of displacements
|
|
TYPE(bec_type) :: becp1(nksq), alphap(3,nksq)
|
|
!
|
|
! ... local variables
|
|
!
|
|
|
|
integer :: na, nb, mu, nu, ikk, ikq, ig, igg, nt, ibnd, ijkb0, &
|
|
ikb, jkb, ih, jh, ipol, is, js, ijs, npwq
|
|
! counter on atoms
|
|
! counter on modes
|
|
! the point k
|
|
! the point k+q
|
|
! counter on G vectors
|
|
! auxiliary counter on G vectors
|
|
! counter on atomic types
|
|
! counter on bands
|
|
! auxiliary variable for counting
|
|
! counter on becp functions
|
|
! counter on becp functions
|
|
! counter on n index
|
|
! counter on m index
|
|
! counter on polarizations
|
|
|
|
real(DP), parameter :: eps = 1.d-12
|
|
|
|
complex(DP), allocatable :: ps1 (:,:), ps2 (:,:,:), aux (:), deff_nc(:,:,:,:)
|
|
real(DP), allocatable :: deff(:,:,:)
|
|
complex(DP), allocatable :: ps1_nc (:,:,:), ps2_nc (:,:,:,:)
|
|
! work space
|
|
|
|
logical :: ok
|
|
|
|
call start_clock ('dvqpsi_us_on')
|
|
if (noncolin) then
|
|
allocate (ps1_nc(nkb , npol, nbnd))
|
|
allocate (ps2_nc(nkb , npol, nbnd , 3))
|
|
allocate (deff_nc(nhm, nhm, nat, nspin))
|
|
else
|
|
allocate (ps1 ( nkb , nbnd))
|
|
allocate (ps2 ( nkb , nbnd , 3))
|
|
allocate (deff(nhm, nhm, nat))
|
|
end if
|
|
allocate (aux ( npwx))
|
|
ikk = ikks(ik)
|
|
ikq = ikqs(ik)
|
|
if (lsda) current_spin = isk (ikk)
|
|
!
|
|
! we first compute the coefficients of the vectors
|
|
!
|
|
if (noncolin) then
|
|
ps1_nc(:,:,:) = (0.d0, 0.d0)
|
|
ps2_nc(:,:,:,:) = (0.d0, 0.d0)
|
|
else
|
|
ps1(:,:) = (0.d0, 0.d0)
|
|
ps2(:,:,:) = (0.d0, 0.d0)
|
|
end if
|
|
do ibnd = 1, nbnd
|
|
IF (noncolin) THEN
|
|
CALL compute_deff_nc(deff_nc,et(ibnd,ikk))
|
|
ELSE
|
|
CALL compute_deff(deff,et(ibnd,ikk))
|
|
ENDIF
|
|
ijkb0 = 0
|
|
do nt = 1, ntyp
|
|
do na = 1, nat
|
|
if (ityp (na) .eq.nt) then
|
|
mu = 3 * (na - 1)
|
|
do ih = 1, nh (nt)
|
|
ikb = ijkb0 + ih
|
|
do jh = 1, nh (nt)
|
|
jkb = ijkb0 + jh
|
|
do ipol = 1, 3
|
|
if ( abs (uact (mu + 1) ) + &
|
|
abs (uact (mu + 2) ) + &
|
|
abs (uact (mu + 3) ) > eps) then
|
|
IF (noncolin) THEN
|
|
ijs=0
|
|
DO is=1,npol
|
|
DO js=1,npol
|
|
ijs=ijs+1
|
|
ps1_nc(ikb,is,ibnd)=ps1_nc(ikb,is,ibnd) + &
|
|
deff_nc(ih,jh,na,ijs) * &
|
|
alphap(ipol, ik)%nc(jkb,js,ibnd)* &
|
|
uact(mu + ipol)
|
|
ps2_nc(ikb,is,ibnd,ipol)= &
|
|
ps2_nc(ikb,is,ibnd,ipol)+ &
|
|
deff_nc(ih,jh,na,ijs) * &
|
|
becp1(ik)%nc(jkb,js,ibnd) * &
|
|
(0.d0,-1.d0) * uact(mu+ipol) * tpiba
|
|
END DO
|
|
END DO
|
|
ELSE
|
|
ps1 (ikb, ibnd) = ps1 (ikb, ibnd) + &
|
|
deff(ih, jh, na) * &
|
|
alphap(ipol, ik)%k(jkb, ibnd) * uact (mu + ipol)
|
|
ps2 (ikb, ibnd, ipol) = ps2 (ikb, ibnd, ipol) +&
|
|
deff(ih,jh,na)*becp1(ik)%k (jkb, ibnd) * &
|
|
(0.0_DP,-1.0_DP) * uact (mu + ipol) * tpiba
|
|
ENDIF
|
|
IF (okvan) THEN
|
|
IF (noncolin) THEN
|
|
ijs=0
|
|
DO is=1,npol
|
|
DO js=1,npol
|
|
ijs=ijs+1
|
|
ps1_nc(ikb,is,ibnd)=ps1_nc(ikb,is,ibnd)+ &
|
|
int1_nc(ih,jh,ipol,na,ijs) * &
|
|
becp1(ik)%nc(jkb,js,ibnd)*uact(mu+ipol)
|
|
END DO
|
|
END DO
|
|
ELSE
|
|
ps1 (ikb, ibnd) = ps1 (ikb, ibnd) + &
|
|
(int1 (ih, jh, ipol,na, current_spin) * &
|
|
becp1(ik)%k (jkb, ibnd) ) * uact (mu +ipol)
|
|
END IF
|
|
END IF
|
|
END IF ! uact>0
|
|
if (okvan) then
|
|
do nb = 1, nat
|
|
nu = 3 * (nb - 1)
|
|
IF (noncolin) THEN
|
|
IF (lspinorb) THEN
|
|
ijs=0
|
|
DO is=1,npol
|
|
DO js=1,npol
|
|
ijs=ijs+1
|
|
ps1_nc(ikb,is,ibnd)= &
|
|
ps1_nc(ikb,is,ibnd)+ &
|
|
int2_so(ih,jh,ipol,nb,na,ijs)* &
|
|
becp1(ik)%nc(jkb,js,ibnd)*uact(nu+ipol)
|
|
END DO
|
|
END DO
|
|
ELSE
|
|
DO is=1,npol
|
|
ps1_nc(ikb,is,ibnd)=ps1_nc(ikb,is,ibnd)+ &
|
|
int2(ih,jh,ipol,nb,na) * &
|
|
becp1(ik)%nc(jkb,is,ibnd)*uact(nu+ipol)
|
|
END DO
|
|
END IF
|
|
ELSE
|
|
ps1 (ikb, ibnd) = ps1 (ikb, ibnd) + &
|
|
(int2 (ih, jh, ipol, nb, na) * &
|
|
becp1(ik)%k (jkb, ibnd) ) * uact (nu + ipol)
|
|
END IF
|
|
enddo
|
|
endif ! okvan
|
|
enddo ! ipol
|
|
enddo ! jh
|
|
enddo ! ih
|
|
ijkb0 = ijkb0 + nh (nt)
|
|
endif
|
|
enddo ! na
|
|
enddo ! nt
|
|
enddo ! nbnd
|
|
!
|
|
! This term is proportional to beta(k+q+G)
|
|
!
|
|
npwq = ngk(ikq)
|
|
if (nkb.gt.0) then
|
|
if (noncolin) then
|
|
call zgemm ('N', 'N', npwq, nbnd*npol, nkb, &
|
|
(1.d0, 0.d0), vkb, npwx, ps1_nc, nkb, (1.d0, 0.d0) , dvpsi, npwx)
|
|
else
|
|
call zgemm ('N', 'N', npwq, nbnd, nkb, &
|
|
(1.d0, 0.d0) , vkb, npwx, ps1, nkb, (1.d0, 0.d0) , dvpsi, npwx)
|
|
end if
|
|
end if
|
|
!
|
|
! This term is proportional to (k+q+G)_\alpha*beta(k+q+G)
|
|
!
|
|
do ikb = 1, nkb
|
|
do ipol = 1, 3
|
|
ok = .false.
|
|
IF (noncolin) THEN
|
|
do ibnd = 1, nbnd
|
|
ok = ok.or.(abs (ps2_nc (ikb, 1, ibnd, ipol) ).gt.eps).or. &
|
|
(abs (ps2_nc (ikb, 2, ibnd, ipol) ).gt.eps)
|
|
end do
|
|
ELSE
|
|
do ibnd = 1, nbnd
|
|
ok = ok.or. (abs (ps2 (ikb, ibnd, ipol) ) .gt.eps)
|
|
enddo
|
|
ENDIF
|
|
if (ok) then
|
|
do ig = 1, npwq
|
|
igg = igk_k (ig,ikq)
|
|
aux (ig) = vkb(ig, ikb) * (xk(ipol, ikq) + g(ipol, igg) )
|
|
enddo
|
|
do ibnd = 1, nbnd
|
|
IF (noncolin) THEN
|
|
call zaxpy(npwq,ps2_nc(ikb,1,ibnd,ipol),aux,1,dvpsi(1,ibnd),1)
|
|
call zaxpy(npwq,ps2_nc(ikb,2,ibnd,ipol),aux,1, &
|
|
dvpsi(1+npwx,ibnd),1)
|
|
ELSE
|
|
call zaxpy (npwq, ps2(ikb,ibnd,ipol), aux, 1, dvpsi(1,ibnd), 1)
|
|
END IF
|
|
enddo
|
|
endif
|
|
enddo
|
|
|
|
enddo
|
|
deallocate (aux)
|
|
IF (noncolin) THEN
|
|
deallocate (ps2_nc)
|
|
deallocate (ps1_nc)
|
|
deallocate (deff_nc)
|
|
ELSE
|
|
deallocate (ps2)
|
|
deallocate (ps1)
|
|
deallocate (deff)
|
|
END IF
|
|
|
|
call stop_clock ('dvqpsi_us_on')
|
|
return
|
|
end subroutine dvqpsi_us_only
|