gamma-only calculation shows HOMO/LUMO at a different location of the 1st BZ?
Posted: Wed Jul 19, 2023 5:46 pm
Hi,
I did a static calculation of graphite at the gamma point, and when I tried to plot the wavefunctions of the HOMO and LUMO bands, I get the pi and pi*, which makes sense from a chemistry perspective. However, looking at the band structure of graphite (https://journals.aps.org/prb/pdf/10.110 ... .69.245419, Fig 2), at the gamma point the VBM and CBM are sigma-type, which makes me confused...if we're only doing the calculation at the gamma point how does it produce a HOMO and a LUMO that should be reflected at the M or L points of the 1st BZ?
Attached is also a figure to illustrate what I mean
thanks!
I did a static calculation of graphite at the gamma point, and when I tried to plot the wavefunctions of the HOMO and LUMO bands, I get the pi and pi*, which makes sense from a chemistry perspective. However, looking at the band structure of graphite (https://journals.aps.org/prb/pdf/10.110 ... .69.245419, Fig 2), at the gamma point the VBM and CBM are sigma-type, which makes me confused...if we're only doing the calculation at the gamma point how does it produce a HOMO and a LUMO that should be reflected at the M or L points of the 1st BZ?
Attached is also a figure to illustrate what I mean
thanks!