[Wannier] Wrong number of k-points with spin-orbit coupling

[elchatz at auth.gr]

Dear Jonathan Yates,

Thank you for your answer.

Do you have any suggestions on the most appropriate configuration for  
a most accurate effective Hamiltonian with SOC, since my bandgap  
changes to indirect in its absence?

Regards



Quoting Jonathan Yates <jonathan.yates at materials.ox.ac.uk>:

> Eleni,
>
>  The error message from pw2wannier90 is not very helpful.
>  The key point is that if you have a system with spin-orbit coupling  
> - then you cannot globally divide the states into spin-up and  
> spin-down.
>  So the keyword  'spin_component = 'up’’ is not valid. Pw2wannier90  
> should probably be improved to give a more sensible error message in  
> this case.
>
>  The wannier90 keyword ‘spin’ is only used when plotting - so it has  
> no effect on the calculations. (I think I should probably change the  
> code so that if spinors=true, you can’t set the spin variable)
>
>  Jonathan
>
>
>> On 24 Jan 2018, at 12:29, elchatz at auth.gr wrote:
>>
>> Hello,
>>
>> I find the wannierization with SOC a bit hard to understand.
>>
>> I am able to run pw2wannier90 with the following configuration:
>>
>> &inputpp
>>  outdir     =  './'
>>  prefix     =  '....'
>>  seedname   =  '...'
>>  write_spn = .true.
>>  write_amn  =  .true.
>>  write_mmn  =  .true.
>> /
>>
>>
>> I can plot the band structure with
>>
>> spinors = .true.
>> spin = up
>>
>> in the win file, which comes up a few eV displaced from the DFT one.
>>
>> When I try to add the following line in the pw2wan file:  
>> 'spin_component = 'up'', I get the following error:
>>
>>  Checking info from wannier.nnkp file
>>  - Real lattice is ok
>>  - Reciprocal lattice is ok
>>  Something wrong!
>>  numk=          64  iknum=          32
>> %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
>>     Error in routine pw2wannier90 (64):
>>     Wrong number of k-points
>> %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
>>
>>     stopping ...
>>
>>
>> with am 8x8x1 k-point mesh both in the DFT and in the Wannier file.
>>
>>
>> Is there something I am missing?
>>
>>
>> Regards,
>>
>>
>>
>>
>> --
>> Dr. Eleni Chatzikyriakou
>> Computational Physics lab
>> Aristotle University of Thessaloniki
>> elchatz at auth.gr - tel:+30 2310 998109
>>
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>
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-- 
Dr. Eleni Chatzikyriakou
Computational Physics lab
Aristotle University of Thessaloniki
elchatz at auth.gr - tel:+30 2310 998109