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Hello All,

I am performing supercell calculations and I have to unfold the obtained band structure. I saw some previous comments about this issue, but did not find them particularly useful.

Has anybody implemented unfolding in VASP? Or perhaps someone can share details how this can be done?

Thanks.

The folding/unfolding can be done between symmetrically equivalent systems. The supercell is usually used in order to introduce some new feature, like a substitution, a vacancy, etc. New features change (decrease) the symmetry of the supercell. In such case the unfolding of the bandstructure to the bandstructure of the irreducible cell is not possible.

Actually, for systems with low density of perturbing agents (substitutions, vacancies, etc.), the unfolding of the bandstructure is not only possible, but even desirable. We have written a code, compatible with VASP, which does exactly this, and we've used it to unfold the band structure of graphene under the influence of different types of intrinsic and extrinsic perturbations [Phys. Rev. B 89, 041407(R) (2014)]. The code is available online at http://www.ifm.liu.se/theomod/compphys/band-unfolding. I hope it helps!