[Wannier] Compiling qe-6.0 with Wannier90 in Library mode

[Vahid Askarpour]

Dear Wannier90 Users,

I posted this to the QE forum but have not heard back yet. Maybe this forum can help me with the following:

I am trying to resolve an energy difference of ~15meV between the VBM of SnSe calculated with EPW and with QE-6.0. EPW runs in the Library mode, while I ran QE in the Standalone mode. So I decided to run QE in the Library mode to track this energy difference.

I am using gcc/5.4.0 and openmpi/2.1.1 with mkl/11.3.4.258. I did a self-consistent run followed by a non self-consistent run. When I ran pw2wannier.x in the Library mode, I get the following error (a similar error http://mailman.qe-forge.org/pipermail/wannier/2016-November/001273.html was unanswered):

 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
     task #        43
     from setup_nnkp : error #         1
      something wrong with num_bands
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%


In the .lib.out, I get no wannier functions:


  Wannier mode is: library        
  Setting up...
  MP grid is   4 x 12 x 12
  - Number of atoms is (  8)
  - Number of wannier functions is (  0)
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
     Error in routine setup_nnkp (1):
      something wrong with num_bands
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
     stopping …


So I tried adding the flag -D__WANLIB to the make.inc of QE although I suspect that the error may not be related to this flag. When compiling, I get the error:

	pw2wannier90.o libpp.a ../../PW/src/libpw.a ../../Modules/libqemod.a ../../FFTXlib/libqefft.a ../../LAXlib/libqela.a /home/vaskarpo/bin/qe-6.0_gcc//clib/clib.a /home/vaskarpo/bin/qe-6.0_gcc//iotk/src/libiotk.a -lmkl_scalapack_lp64 -lmkl_blacs_openmpi_lp64   -lmkl_gf_lp64  -lmkl_sequential -lmkl_core    
pw2wannier90.o: In function `run_wannier_':
/home/vaskarpo/bin/qe-6.0_gcc/PP/src/pw2wannier90.f90:636: undefined reference to `wannier_run_'
pw2wannier90.o: In function `setup_nnkp_':
/home/vaskarpo/bin/qe-6.0_gcc/PP/src/pw2wannier90.f90:511: undefined reference to `wannier_setup_'
collect2: error: ld returned 1 exit status
make[2]: *** [Makefile:140: pw2wannier90.x] Error 1
make[2]: Leaving directory '/home/vaskarpo/bin/qe-6.0_gcc/PP/src'
make[1]: *** [Makefile:7: all] Error 1
make[1]: Leaving directory '/home/vaskarpo/bin/qe-6.0_gcc/PP'
make: *** [Makefile:92: pp] Error 1

My SnSe.pw2wan.lib.in is 

&inputpp 
   outdir = './'
   prefix = 'SnSe'
   seedname = 'SnSe.lib'
   spin_component = 'none'
   write_mmn = .true.
   write_amn = .true.
   write_unk = .false.
   wan_mode = ‘library’
/

My SnSe.lib.win is

num_bands=20
num_wann=20
num_iter    = 5000

begin atoms_frac
Sn       0.882841736   0.250000000   0.602195343
Sn       0.617158264   0.750000000   0.102195343
Sn       0.382841736   0.250000000   0.897804657
Sn       0.117158264   0.750000000   0.397804657
Se       0.142813748   0.250000000   0.976427467
Se       0.357186252   0.750000000   0.476427467
Se       0.642813748   0.250000000   0.523572533
Se       0.857186252   0.750000000   0.023572533
end atoms_frac

begin projections
Sn:s
Se:s;px;py;pz
end projections

begin unit_cell_cart
bohr
21.34350847 0 0
0 7.7450832 0
0 0 8.23579698
end_unit_cell_cart

mp_grid : 4 12 12

begin kpoints
  0.00000000  0.00000000  0.00000000  1.736111e-03 
  0.00000000  0.00000000  0.08333333  1.736111e-03 
  0.00000000  0.00000000  0.16666667  1.736111e-03 
……..
end kpoints

I am hoping to run Wannier90 in the Library mode outside EPW to track the cause of the energy difference between the Library mode and the Standalone mode. How can I get QE-6.0/pw2wannier.x to run in the Library mode?

Thank you,

Vahid

Vahid Askarpour
Department of Physics and Atmospheric Science
Dalhousie University,
Halifax, NS, Canada