allocate_wfc.f90

!
! Copyright (C) 2001-2024 Quantum ESPRESSO Foundation
! 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 allocate_wfc_k()
  !----------------------------------------------------------------------------
  !! Dynamical allocation of k-point-dependent arrays: 
  !! wavefunctions, betas kinetic energy, k+G indices. 
  !! Computes max no. of plane waves \(\text{npwx}\) and k+G indices 
  !! \(\text{igk_k}\) (needs G-vectors and cutoff \(\text{gcutw}\)).  
  !! Requires dimensions \(\text{nbnd}\), \(\text{npol}\)
  !! Requires that k-points are set up and distributed (if parallelized).
  !
  USE wavefunctions,    ONLY : allocate_wfc
  USE wvfct,            ONLY : npwx, g2kin, nbnd
  USE uspp,             ONLY : vkb, nkb
  USE gvecw,            ONLY : gcutw
  USE gvect,            ONLY : ngm, g
  USE klist,            ONLY : xk, nks, init_igk
  USE noncollin_module, ONLY : npol
  !
  IMPLICIT NONE
  !
  INTEGER, EXTERNAL :: n_plane_waves
  !
  !   calculate number of PWs for all kpoints
  !
  npwx = n_plane_waves( gcutw, nks, xk, g, ngm )
  !
  !   compute indices j=igk(i) such that (k+G)_i = k+G_j, for all k
  !   compute number of plane waves ngk(ik) as well
  !
  CALL init_igk( npwx, ngm, g, gcutw )
  !
  CALL allocate_wfc( npwx, npol, nbnd )
  !
  !   beta functions
  !
  ALLOCATE( vkb(npwx,nkb) )
  !$acc enter data create(vkb) 
  !
  !   g2kin contains the kinetic energy \hbar^2(k+G)^2/2m
  !
  ALLOCATE( g2kin(npwx) )
  !$acc enter data create(g2kin) 
  !
  !
  RETURN
  !
END SUBROUTINE allocate_wfc_k