This depends on which bandgap you want? 1) An indirect bandgap Here you should take the lowest unoccupied state for *all* kpoints, and the highest occupied state for *all* kpoints. Then the difference between the two is the indirect bandgab. 2) A direct bandgap Here you should take the lowest unoccupied state for ONE kpoint, and the highest occupied state for the same kpoint. The difference between the two is the direct bandgap for that k-point. You then repeat this for *all* kpoints and take the lowest one of them all. That is the direct bandgap.
Note however, that it is important you have a sufficiently dense kgrid to get reasonable results. This is of course material dependent. Den ons. 31. mar. 2021 kl. 22.04 skrev El-abed Haidar < ehai2...@uni.sydney.edu.au>: > Good afternoon, > > 1. I was wondering if I want to extract the bandgap other than from > the PDOS, is it possible to do so from the EIG file? > 2. I heard it before but I am not sure by looking at the different k > points in the EIG file, which k pt to choose? Is it based on the band > structure and closest to the Fermi energy? > > Thank you and looking forward to everyones’ thoughts > > Thank you, > > El-abed Haidar | Doctor of Philosophy (Science) > Condensed Matter Theory (CMT) Group| School of Physics > THE UNIVERSITY OF SYDNEY | NSW | 2006 > > > > -- > SIESTA is supported by the Spanish Research Agency (AEI) and by the > European H2020 MaX Centre of Excellence (http://www.max-centre.eu/) > -- Kind regards Nick
-- SIESTA is supported by the Spanish Research Agency (AEI) and by the European H2020 MaX Centre of Excellence (http://www.max-centre.eu/)
