[Wannier] Error in Plotting Si wannier functions

[Jonathan Yates]

On 9 Jan 2010, at 20:52, Vahid Askarpour wrote:

> Dear Wannier Users,
>
> I have followed the tutorial examples in tutorial_files/w90-ex1.  
> Everything works fine until the last stage when I ask to plot the  
> wannier functions. In the .wout file, I get:
>
> *---------------------------------------------------------------------------*
>  |                                
> PLOTTING                                    |
>   
> *---------------------------------------------------------------------------*
>  WARNING: mismatch in fileUNK00001.1
>     ix=   24   iy=   24   iz=    1   ik=   12 nbnd=   20
>    ngx=   24  ngy=   24  ngz=    1  kpt=    1bands=   12
>  Exiting.......
>  plot_wannier
>
>
> I would appreciate any comments.

Vahid,

  It looks like you are following the tutorial from the 2007 cecam  
workshop on Wannier functions. I think you'd probably find the  
tutorial that comes with the W90 distribution better (more examples,  
more attention paid to the instructions etc).
Although in any case the example w90-ex1 should work. It seems to work  
fine for me:

pw2wannier90.x < silicon.scf  > scf.out
pw2wannier90.x < silicon.nscf > nscf.out
wannier90.x -pp silicon
pw2wannier90.x < silicon.pw2wan > pw2wan.out
wannier90.x silicon

The only changes I made to the files was to change outdir in  
silicon.scf, silicon.nscf and silicon.pw2wan and to add  
'wannier_plot=true' into silicon.win.

There is something odd about your error message. W90 opens the first  
unk file, reads the fft grid dimension (ngx, ngy, ngz), closes the  
file and allocates some arrays. It then reads each unk file in turn,  
checking that it finds the right k-point and number of bands.
  In your case it failed as it found 20 bands in unk - not the 12 it  
expected.
The odd thing is that your fft grid appears to be 24x24x1 (not  
24x24x24).

  So I suspect your UNK file is wrong, or corrupted in someway. I  
don't know how that could have happened. Try again - follow the W90  
tutorial, try other examples (A slightly more usual way this might  
possibly occur is if you used a different compiler for pwscf and  
wannier90)

If you still have this problem let us know - but tell us the version  
of pwscf/wannier90 and the exact commands you issue.

  Jonathan




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