TABLE OF CONTENTS

ABINIT/gwls_GWanalyticPart [ Modules ]

[ Top ] [ Modules ]

NAME

 gwls_GWanalyticPart

FUNCTION

  .

COPYRIGHT

 Copyright (C) 2009-2018 ABINIT group (JLJ, BR, MC)
 This file is distributed under the terms of the
 GNU General Public License, see ~abinit/COPYING
 or http://www.gnu.org/copyleft/gpl.txt .

PARENTS

CHILDREN

SOURCE

21 #if defined HAVE_CONFIG_H
22 #include "config.h"
23 #endif
24 
25 #include "abi_common.h"
26 
27 
28 
29 module gwls_GWanalyticPart
30 !----------------------------------------------------------------------------------------------------
31 ! This module contains routines to compute the contribution to the GW correlation energy coming
32 ! from the analytic integral of the trial frequency function.
33 !----------------------------------------------------------------------------------------------------
34 ! local modules
35 use m_gwls_utility
36 use gwls_wf
37 use gwls_hamiltonian
38 use gwls_lineqsolver
39 use gwls_GWlanczos
40 use gwls_GenerateEpsilon
41 use gwls_LanczosBasis
42 use gwls_model_polarisability
43 use gwls_polarisability
44 !use gwls_ComplementSpacePolarizability
45 use gwls_GWlanczos
46 use gwls_TimingLog
47 
48 ! abinit modules
49 use defs_basis
50 use m_profiling_abi
51 
52 implicit none
53 save
54 private

m_hamiltonian/get_projection_band_indices [ Functions ]

[ Top ] [ m_hamiltonian ] [ Functions ]

NAME

  get_projection_band_indices

FUNCTION

  .

INPUTS

OUTPUT

PARENTS

      gwls_Projected_AT

CHILDREN

SOURCE

 92 subroutine get_projection_band_indices(omega,band_index_below, band_index_above)
 93 !----------------------------------------------------------------------------------------------------
 94 ! This subroutine computes the band indices necessary for properly projecting the Sternheimer equations
 95 ! where
 96 !                Pe : projection on states such that epsilon_n < omega
 97 !                Qe : projection on states such that epsilon_n > omega
 98 !----------------------------------------------------------------------------------------------------
 99 
100 !This section has been created automatically by the script Abilint (TD).
101 !Do not modify the following lines by hand.
102 #undef ABI_FUNC
103 #define ABI_FUNC 'get_projection_band_indices'
104 !End of the abilint section
105 
106 implicit none
107 
108 real(dp),intent(in)  :: omega 
109 integer, intent(out) :: band_index_below, band_index_above
110 
111 ! *************************************************************************
112 
113 ! First, find the indices for the projections
114 
115 band_index_below = 1
116 ! it is assumed that the eigenvalues are sorted. As soon as the current eigenvalue
117 ! is equal or larger than epsilon_e,  exit!
118 do
119 if ( omega - eig(band_index_below) <= 1.0e-8 ) exit
120 band_index_below = band_index_below + 1
121 
122 if (band_index_below > size(eig)) then
123 
124   write(std_out,*) '************************************************************'
125   write(std_out,*) '***    ERROR IN ROUTINE get_projection_band_indices      ***'
126   write(std_out,*) '***                                                      ***'
127   write(std_out,*) '***    The index of the DFT eigenvalue larger than       ***'
128   write(std_out,*) '***    the target frequency is larger than the number    ***'
129   write(std_out,*) '***    of explicitly calculated DFT eigenvalues.         ***'
130   write(std_out,*) '***    The computation cannot go on to produce a         ***'
131   write(std_out,*) '***    meaningful result: review your input!             ***'
132   write(std_out,*) '***                                                      ***'
133   write(std_out,*) '***               program stops.                         ***'
134   write(std_out,*) '************************************************************'
135   stop
136 end if
137 end do
138 ! We have overshooted in order to exit the do loop , so decrement by 1
139 band_index_below = band_index_below - 1
140 
141 ! band_index_below  is now the index of the highest eigenvalue BELOW omega
142 ! NOTE THAT band_index_below = 0 if omega is smaller than all eigenvalues!
143 ! A test should be performed on the indices obtained from this routine
144 
145 band_index_above = band_index_below+1
146 do
147 if ( eig(band_index_above)-omega > 1.0e-8 ) exit
148 band_index_above = band_index_above + 1
149 end do
150 ! band_index_above is now the index of the lowest eigenvalue ABOVE eig(e)
151 band_index_above = band_index_above - 1
152 ! band_index_above is now the highest index with eigenvalue equal to eig(e).
153 ! This is the correct index to remove the states with energy <= eig(e)
154 
155 end subroutine get_projection_band_indices