mirror of https://gitlab.com/QEF/q-e.git
60 lines
1.8 KiB
Fortran
60 lines
1.8 KiB
Fortran
!
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! Copyright (C) 2001 PWSCF group
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! This file is distributed under the terms of the
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! GNU General Public License. See the file `License'
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! in the root directory of the present distribution,
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! or http://www.gnu.org/copyleft/gpl.txt .
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!
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!-----------------------------------------------------------------------
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subroutine set_d3irr
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!-----------------------------------------------------------------------
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!
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! It computes a basis for all the irreducible representations of the
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! group of the crystal, which are contained in the representation
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! which has as basis the displacement vectors.
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! This basis will be used for those quantities that depend on the
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! q=0 perturbation.
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!
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! Receives in input: nsymg0, s, invs, irt, rtau
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! Calculates: ug0, tg0, npertg0, nirrg0, irgq
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!
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! NB: It assumes that the phonon calculation for the q=0 case, has been
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! performed with iswitch=-2. If this is not the case the following
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! routine does not work.
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!
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#include "machine.h"
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use pwcom
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use phcom
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use d3com
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implicit none
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integer :: w_nsymq, w_irotmq
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! work array
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! work array
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real (8) :: zero (3), w_gi (3, 48), w_gimq (3)
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! a null vector
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! work array
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complex (8) :: w_tmq (3, 3, 3 * nat)
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! work array
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logical :: w_minus_q
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! work array
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call setv (3, 0.d0, zero, 1)
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w_minus_q = .true.
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if (nsymg0.gt.1) then
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call io_pattern(fild0rho,nirrg0,npertg0,ug0,-1)
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call set_sym_irr (nat, at, bg, zero, s, invs, nsymg0, rtau, irt, &
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irgq, w_nsymq, w_minus_q, w_irotmq, tg0, w_tmq, ug0, npertg0, &
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nirrg0, w_gi, w_gimq, iverbosity)
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else
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call set_irr_nosym (nat, at, bg, zero, s, invs, nsymg0, rtau, &
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irt, irgq, w_nsymq, w_minus_q, w_irotmq, tg0, w_tmq, ug0, &
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npertg0, nirrg0, w_gi, w_gimq, iverbosity)
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endif
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return
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end subroutine set_d3irr
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