[Wannier] The fermi level downshifted below VBM when using GW method

[Jonathan Yates]

On 19 Jun 2013, at 17:00, 吕红艳 <honglv28 at gmail.com> wrote:

> Hello, 
> I am calculating the band structure of bulk Bi2Te3 using GW method. I have recompiled the vasp code with vasp2wannier included and the band structure was calculated using wannier interpolation. The topology of the band structure with GW is almost same as the one without GW, but the Fermi level is not correct. That is, the Fermi level is now ~0.25 eV below the original VBM site. Could anyone give me some suggestion?

You should think about how your value of the Fermi energy is calculated. The Fermi energy should be consistent with the set of bands you have - i.e. different between LDA and GW. I think bulk Bi2Te3 should have a band gap in both LDA and GW, so you could simply compute the position of the Fermi level from band counting.

As a general point, it is probably worth checking that for an LDA calculation your wannier interpolated bands are a good match for those from the full electronic-structure calculation.

 Yours
  Jonathan



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