How to find HOMO-LUMO or conduction-valence band energy levels of any material?

Hello,

I could easily find the bang gaps of materials from the database but unfortunately i could not extract the HOMO-LUMO or conduction-valence band energy levels. Is there any way to do it?

Thank you

Cagla

Hi Cagla,

You can get the bandstructure object of a given material, from which you can get some info about the wavevector corresponding to the valence band maximum or the conduction band minimum, but we don’t yet offer band edge positions against a fixed reference (e.g. vacuum) if that’s what you’re looking for. We have been collecting these data recently, though, and are hoping to disseminate in the near future.

Hello Joseph

Thank you for your answer. I looked to the wavevectors of the materials but it is always zero for the valence band maximum. Hence, as I understood, there is no way to calculate or extract the HOMO-LUMO or conduction-valence band energy levels from this database, right? I need the band edge positions. When do you think the band edge positions will be added to the database?

Thank you

Hi Cagla,

Are you just looking for the band gap by any chance? The solid state analogues to the HOMO and LUMO are valence band maximum and the conduction band minimum. The difference is the band gap, which we report. The band edges provide a way to reference this to vacuum. These calculations are VERY expensive, and we are unlikely to perform them for all the materials in the Materials Project.