[Wannier] bug in wannier90?

[Jonathan Yates]

On Thu, 3 Jul 2008, Alexandre Volgin wrote:

> Dear Jonathan,
>
> I think there are some problems with wannier when I am launching it in a 
> library mode:
> each time I have an error message:
> " Exiting.......
> plot_wannier: file UNK00001.1  not found "
> With an option wannier_plot=.true UNK00* files are not created (even if I ask 
> it in pw2wan input file). So first I tried to launch calculations without 
> "wannier_plot" option, after what files UNK have appeared. But I must launch 
> wannier one more time to visualize them... Is it normal?

Alexandre,

  I understand the problem - it is actually a "bug" in pw2wannier90 not in 
wannier90 itself.

  Here is part of pw2wannier90.f90 (comment lines omitted)

   if(wan_mode.eq.'library') then
      !
      call setup_nnkp
      call openfil_pp
      call ylm_expansion
      call compute_amn
      call compute_mmn
      call write_band
      call run_wannier                     ! <- this runs w90
      if(write_unk) call write_plot        ! <- this writes the UNK
      call lib_dealloc
      call stop_pp
      !
   endif

So you see we run w90 _before_ writing the UNK files. What I think we need 
to do is reverse the position of the two commented lines ie

      if(write_unk) call write_plot        ! <- this writes the UNK
      call run_wannier                     ! <- this runs w90

  Then plotting works fine in library mode.

Arash, Stefano: Can you see any problems with making this change? - 
otherwise we should check it into the cvs.


  Jonathan


-- 
Dr Jonathan Yates         |    Theory of Condensed Matter Group
Corpus Christi College    |    Cavendish Laboratory
Cambridge, CB2 1RH, UK    |    Cambridge, CB3 OHE, UK
email jry20 at cam.ac.uk     |    Tel +44 (0)1223 337461