Fixed a bug in turboTDDFT which was appearing if empty states were also computed.

This bug is related to the variable nwordwfc, which depends on the number of bands.
In turboTDDFT if empty states are computed (which is not needed for turbo_lanczos.x, but allowed,
and in fact the code will simply skip empty states), the global variable nbnd is set equal to 
nbnd_occ, i.e. only occupied bands (this is not my idea), which is bad, because global 
variables should not change their values. Due to such a confusion, I introduced this bug
some time ago. Now this is fixed.  


git-svn-id: http://qeforge.qe-forge.org/svn/q-e/trunk/espresso@12603 c92efa57-630b-4861-b058-cf58834340f0

Doc/release-notes

@@ -23,6 +23,7 @@ Fixed in 6.0 version:
     (courtesy Marton Voros) (commit 12426)
   * PHonon: support for Goedecker-Hutter-Teter pseudopotentials was missing
     (courtesy of Sebastiano Caravati)
+  * turboTDDFPT: Problem if empty states were also computed. 
 
 Incompatible changes in 6.0 version:
 

TDDFPT/src/lr_dav_main.f90

@@ -141,7 +141,7 @@ PROGRAM lr_dav_main
 CONTAINS
   SUBROUTINE lr_print_preamble()
 
-    USE lr_variables, ONLY : no_hxc, itermax
+    USE lr_variables, ONLY : no_hxc, d0psi_rs
     USE uspp,         ONLY : okvan
     USE funct,        only : dft_is_hybrid
     USE martyna_tuckerman,   ONLY : do_comp_mt
@@ -182,9 +182,10 @@ CONTAINS
  
     IF (no_hxc)  THEN
        WRITE(stdout,'(5x,"No Hartree/Exchange/Correlation")')
-    ELSEIF (dft_is_hybrid()) THEN
+    ELSEIF (dft_is_hybrid() .AND. .NOT.d0psi_rs) THEN
        WRITE(stdout, '(/5x,"Use of exact-exchange enabled. Note the EXX correction to the [H,X]", &
-            &/5x,"commutator is NOT included hence the f-sum rule will be violated.")')
+                     & /5x,"commutator is NOT included hence the f-sum rule will be violated.",   &
+                     & /5x,"You can try to use the variable d0psi_rs=.true. (see the documentation).")' )
     ENDIF
   END SUBROUTINE lr_print_preamble
 

TDDFPT/src/lr_init_nfo.f90

@@ -21,8 +21,8 @@ SUBROUTINE lr_init_nfo()
   USE klist,                ONLY : nks,xk,ngk,igk_k
   USE wvfct,                ONLY : nbnd
   USE realus,               ONLY : real_space
-  USE lr_variables,         ONLY : lr_verbosity, eels, nwordd0psi, &
+  USE lr_variables,         ONLY : lr_verbosity, eels, restart, &
-                                   nwordrestart, restart, size_evc, tmp_dir_lr
+                                   size_evc, tmp_dir_lr
   USE io_global,            ONLY : stdout
   USE constants,            ONLY : tpi, eps8
   USE noncollin_module,     ONLY : npol
@@ -91,15 +91,12 @@ SUBROUTINE lr_init_nfo()
      !
   ENDIF
   !
-  ! The length of the arrays d0psi, evc1 etc.
-  !
-  nwordd0psi   = 2 * nbnd * npwx * npol * nksq
-  nwordrestart = 2 * nbnd * npwx * npol * nksq
-  nwordwfc     =     nbnd * npwx * npol 
-  !
   ! 2) EELS-specific operations
   !
   IF (eels) THEN
+     !
+     size_evc = nbnd * npwx * npol * nksq
+     nwordwfc = nbnd * npwx * npol
      !
      ! Open file to read the wavefunctions at k and k+q points 
      ! after the nscf calculation.
@@ -112,8 +109,6 @@ SUBROUTINE lr_init_nfo()
         CALL errore ('lr_init_nfo', 'file '//trim(prefix)//'.wfc not found', 1)
      ENDIF
      !
-     size_evc = nksq * nbnd * npwx * npol 
-     !
      ! If restart=.true. recalculate the small group of q.
      !
      IF (restart) CALL lr_smallgq (xq)

TDDFPT/src/lr_main.f90

@@ -307,7 +307,7 @@ CONTAINS
  
 SUBROUTINE lr_print_preamble()
     
-    USE lr_variables,        ONLY : no_hxc
+    USE lr_variables,        ONLY : no_hxc, d0psi_rs
     USE uspp,                ONLY : okvan
     USE funct,               ONLY : dft_is_hybrid
     USE martyna_tuckerman,   ONLY : do_comp_mt
@@ -338,7 +338,7 @@ SUBROUTINE lr_print_preamble()
     !
     IF (no_hxc)  THEN
        WRITE(stdout,'(5x,"No Hartree/Exchange/Correlation")')
-    ELSEIF (dft_is_hybrid()) THEN
+    ELSEIF (dft_is_hybrid() .AND. .NOT.d0psi_rs) THEN
        WRITE(stdout, '(/5x,"Use of exact-exchange enabled. Note the EXX correction to the [H,X]", &
                      & /5x,"commutator is NOT included hence the f-sum rule will be violated.",   &
                      & /5x,"You can try to use the variable d0psi_rs=.true. (see the documentation).")' )

TDDFPT/src/lr_read_d0psi.f90

@@ -1,5 +1,5 @@
 !
-! Copyright (C) 2001-2015 Quantum ESPRESSO group
+! 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,
@@ -17,10 +17,12 @@ SUBROUTINE lr_read_d0psi()
   !
   USE klist,                ONLY : nks,degauss
   USE io_files,             ONLY : prefix, diropn, tmp_dir, wfc_dir
-  USE lr_variables,         ONLY : d0psi, d0psi2, n_ipol, LR_polarization, lr_verbosity, &
+  USE lr_variables,         ONLY : d0psi, d0psi2, n_ipol, LR_polarization, &
-                                 & nwordd0psi, iund0psi, eels
+                                   & lr_verbosity, nwordd0psi, iund0psi, eels
   USE wvfct,                ONLY : nbnd, npwx, et
   USE io_global,            ONLY : stdout
+  USE qpoint,               ONLY : nksq
+  USE noncollin_module,     ONLY : npol
   !
   IMPLICIT NONE
   !
@@ -35,6 +37,8 @@ SUBROUTINE lr_read_d0psi()
     WRITE(stdout,'("<lr_read_d0psi>")')
   endif
   !
+  nwordd0psi = 2 * nbnd * npwx * npol * nksq
+  !
   ! This is a parallel read, done in wfc_dir
   !
   tmp_dir_saved = tmp_dir
@@ -101,5 +105,7 @@ SUBROUTINE lr_read_d0psi()
   !
   tmp_dir = tmp_dir_saved
   !
+  RETURN
+  !
 END SUBROUTINE lr_read_d0psi
 !-----------------------------------------------------------------------

TDDFPT/src/lr_read_wf.f90

@@ -66,8 +66,6 @@ SUBROUTINE lr_read_wf()
      CALL normal_read()
   ENDIF
   !
-  !WRITE(stdout,'(5x,"Finished reading wfc.")')
-  !
   IF (.NOT.eels) evc(:,:) = evc0(:,:,1)
   !
   IF ( dft_is_hybrid() ) THEN
@@ -116,9 +114,11 @@ SUBROUTINE normal_read()
   WRITE( stdout, '(/5x,"Normal read")' )
   !
   use_tg = dffts%have_task_groups
-  size_evc = nksq * nbnd * npwx * npol
   incr = 2
   !
+  size_evc = nbnd * npwx * npol * nksq
+  nwordwfc = nbnd * npwx * npol
+  !
   ! Read in the ground state wavefunctions.
   ! This is a parallel read, done in wfc_dir.
   !
@@ -334,7 +334,8 @@ SUBROUTINE virt_read()
      !
   ENDIF
   !
-  size_evc = nksq * nbnd_occ(1) * npwx * npol
+  size_evc = nbnd_occ(1) * npwx * npol * nksq
+  nwordwfc = nbnd * npwx * npol                 ! nbnd > nbnd_occ(1)
   !
   ! Read in the ground state wavefunctions
   ! This is a parallel read, done in wfc_dir
@@ -435,6 +436,8 @@ SUBROUTINE virt_read()
   !
   nbnd = nbnd_occ(1)
   !
+  nwordwfc = nbnd * npwx * npol ! needed for EXX
+  !
   CALL deallocate_bec_type(becp)
   CALL allocate_bec_type ( nkb, nbnd, becp )
   !

TDDFPT/src/lr_restart.f90

@@ -25,14 +25,15 @@ SUBROUTINE lr_restart(iter_restart,rflag)
                                    lr_verbosity, charge_response, LR_polarization, n_ipol, &
                                    eels, sum_rule
   USE charg_resp,           ONLY : resonance_condition, rho_1_tot,rho_1_tot_im
-  USE wvfct,                ONLY : nbnd
+  USE wvfct,                ONLY : nbnd, npwx
   USE becmod,               ONLY : bec_type, becp, calbec
   USE uspp,                 ONLY : vkb 
   USE io_global,            ONLY : ionode
   USE mp,                   ONLY : mp_bcast
   USE mp_world,             ONLY : world_comm
   USE fft_base,             ONLY : dfftp
-  USE noncollin_module,     ONLY : nspin_mag
+  USE noncollin_module,     ONLY : nspin_mag, npol
+  USE qpoint,               ONLY : nksq
 
   IMPLICIT NONE
   !
@@ -180,6 +181,8 @@ SUBROUTINE lr_restart(iter_restart,rflag)
   ! Note: Restart files are always in outdir
   ! Reading Lanczos vectors
   !
+  nwordrestart = 2 * nbnd * npwx * npol * nksq
+  !
   CALL diropn ( iunrestart, 'restart_lanczos.'//trim(int_to_char(LR_polarization)), nwordrestart, exst)
   !
   CALL davcio(evc1(:,:,:,1),nwordrestart,iunrestart,1,-1)

TDDFPT/src/lr_solve_e.f90

@@ -38,6 +38,7 @@ SUBROUTINE lr_solve_e
   USE realus,               ONLY : real_space, real_space_debug 
   USE control_lr,           ONLY : alpha_pv
   USE qpoint,               ONLY : nksq
+  USE noncollin_module,     ONLY : npol
   !
   IMPLICIT NONE
   INTEGER :: ibnd, ik, is, ip
@@ -129,6 +130,8 @@ SUBROUTINE lr_solve_e
   ! Writing of d0psi to the file. 
   ! This is a parallel writing, done in wfc_dir 
   !
+  nwordd0psi = 2 * nbnd * npwx * npol * nksq
+  !
   tmp_dir_saved = tmp_dir
   !
   IF ( wfc_dir /= 'undefined' ) tmp_dir = wfc_dir

TDDFPT/src/lr_write_restart.f90

@@ -27,9 +27,10 @@ SUBROUTINE lr_write_restart()
   USE fft_base,             ONLY : dfftp
   USE io_global,            ONLY : ionode, stdout
   USE klist,                ONLY : nks, nelec
-  USE noncollin_module,     ONLY : nspin_mag, noncolin
+  USE noncollin_module,     ONLY : nspin_mag, noncolin, npol
-  use lsda_mod,             only : nspin
+  use lsda_mod,             ONLY : nspin
   USE cell_base,            ONLY : alat, omega
+  USE qpoint,               ONLY : nksq
   !
   IMPLICIT NONE
   CHARACTER(len=6), EXTERNAL :: int_to_char
@@ -165,7 +166,7 @@ SUBROUTINE lr_write_restart()
     !
     ! Writing wavefuncion files for restart
     !
-    !nwordrestart = 2 * nbnd * npwx * nks
+    nwordrestart = 2 * nbnd * npwx * npol * nksq
     !
     CALL diropn ( iunrestart, 'restart_lanczos.'//trim(int_to_char(LR_polarization)), nwordrestart, exst)
     !

TDDFPT/src/make.depend

@@ -373,8 +373,10 @@ lr_psym_eels.o : ../../Modules/fft_base.o
 lr_psym_eels.o : ../../Modules/kind.o
 lr_psym_eels.o : ../../Modules/mp_global.o
 lr_psym_eels.o : ../../Modules/noncol.o
+lr_read_d0psi.o : ../../LR_Modules/lrcom.o
 lr_read_d0psi.o : ../../Modules/io_files.o
 lr_read_d0psi.o : ../../Modules/io_global.o
+lr_read_d0psi.o : ../../Modules/noncol.o
 lr_read_d0psi.o : ../../PW/src/pwcom.o
 lr_read_d0psi.o : lr_variables.o
 lr_read_wf.o : ../../FFTXlib/fft_interfaces.o
@@ -432,6 +434,7 @@ lr_readin.o : ../../iotk/src/iotk_module.o
 lr_readin.o : lr_charg_resp.o
 lr_readin.o : lr_dav_variables.o
 lr_readin.o : lr_variables.o
+lr_restart.o : ../../LR_Modules/lrcom.o
 lr_restart.o : ../../Modules/becmod.o
 lr_restart.o : ../../Modules/control_flags.o
 lr_restart.o : ../../Modules/fft_base.o
@@ -489,6 +492,7 @@ lr_solve_e.o : ../../Modules/ions_base.o
 lr_solve_e.o : ../../Modules/kind.o
 lr_solve_e.o : ../../Modules/mp.o
 lr_solve_e.o : ../../Modules/mp_global.o
+lr_solve_e.o : ../../Modules/noncol.o
 lr_solve_e.o : ../../Modules/recvec.o
 lr_solve_e.o : ../../Modules/uspp.o
 lr_solve_e.o : ../../Modules/wavefunctions.o
@@ -533,6 +537,7 @@ lr_us.o : ../../PW/src/realus.o
 lr_us.o : lr_variables.o
 lr_variables.o : ../../Modules/control_flags.o
 lr_variables.o : ../../Modules/kind.o
+lr_write_restart.o : ../../LR_Modules/lrcom.o
 lr_write_restart.o : ../../Modules/cell_base.o
 lr_write_restart.o : ../../Modules/fft_base.o
 lr_write_restart.o : ../../Modules/io_files.o