[Wannier] Param_read error

[Jonathan Yates]

On 18 Oct 2014, at 17:00, SRKC Sharma Yamijala <sharmajncasr at gmail.com> wrote:

> Dear Wannier90 member,
> 
> I am working on SrVO3. I have successfully ran till pw2wannier.x file but while trying to run the wannier90.x executable I got the below error showing some mismatch in srvo3.eig. I couldn't find any wrong in my input files. I have carefully checked but I am not able to find the error.

First - thanks for providing the full files - it made it quick to diagnose the problem:

The issue is the line in pw2wannier90
IF (ionode) WRITE (iun_band,'(2i5,f18.12)') ibnd1, ikevc, et(ibnd,ik)*rytoev

So we are writing the kpoint number into a 5 integer space. However, you have a really dense kpoint grid, and this takes all the width, resulting in

    1 9999    6.836438301247
    2 9999    8.370312708611
    3 9999    8.380224441343
    110000    6.719602639027
    210000    8.377174476130
    310000    8.381667816813

i.e. the first two integers have merged. To avoid rerunning your calculation you can use an editor to insert an extra space. For future runs you can modify the fortran source of pw2wannier90.f90 to
 IF (ionode) WRITE (iun_band,'(i5,x,i5,f18.12)') ibnd1, ikevc, et(ibnd,ik)*rytoev
or
 IF (ionode) WRITE (iun_band,'(i0,x,i0,f18.12)') ibnd1, ikevc, et(ibnd,ik)*rytoev

Note that you will need to make the same changes to your amn file (and/or the appropriate formatting statement in pw2wannier90.f90)

This is something we should fix. However, I am curious as to why you need to use a 25x25x25 grid. That is really very dense - usually you would sample the Brillouin Zone quite coarsely when forming the WF, and use wannier interpolation to sample much more finely. 

 Jonathan


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