[Wannier] bands structure of graphene

[Jonathan Yates]

On 13 May 2012, at 04:20, Hua-Qing Huang wrote:

> Dear all,
>  Recently，I want to calculate MLWF of graphene and I have got the sp2-like and 
> pz-like MLWF. However, I found that the band strucutre obtained using MLWF 
> interpolation doesn't agree well with the band structure obtained form first-
> principles calculation (pwscf). What's worse, there is a gap near the fermi 
> level, which should be a Dirac cone.
>  I have tried different dis_win_max, dis_froz_max, but still can't solve the 
> problem. So could you give me some suggestions?

Dear Huaqing,

Without seeing more information (input/output) it is difficult to say what the problem is.

My general advice would be to first start with example10 which is AB stacked graphite. Check this gives what you expect. Then remove one of the planes of atoms. The MLWF should be very similar - as should the interpolated band structure. You could then increase the plane separation.
 If this works (and it has for me in the past), and your inputs don't, you should be able to work out what went wrong.


Jonathan


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Department of Materials, University of Oxford, Parks Road, Oxford, OX1 3PH, UK
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