stretching of the bands
Posted: Sat Mar 04, 2023 6:06 am
Dear users and developers,
I have a number of questions about the stretching of the conduction (Mc) and valence (Mv) bands obtained from the linear fit of the quasiparticle energies in terms of Kohn-Sham energies:
1) Does Mc & Mv being closer to one indicate that more accurate calculations have been done? For example, as can be seen in the attached figures, when I consider only the highest 5 valence bands in GW calculations, Mv becoms 0.5, while for 6 valence bands, Mv is approximately one.
Dose this mean that the second calculation is correct?
2) We know that in GW calculations, the amount of energy correction of the conduction band is higher than that of the valence band. Does this also apply to the stretching of the bands, that is, the stretching of the conduction band should be greater than the stretching of the valence band? Because in my calculations Mv=1.028 is obtained more than Mc=0.908.
Thanks and Regards,
Mitra Helmi
I have a number of questions about the stretching of the conduction (Mc) and valence (Mv) bands obtained from the linear fit of the quasiparticle energies in terms of Kohn-Sham energies:
1) Does Mc & Mv being closer to one indicate that more accurate calculations have been done? For example, as can be seen in the attached figures, when I consider only the highest 5 valence bands in GW calculations, Mv becoms 0.5, while for 6 valence bands, Mv is approximately one.
Dose this mean that the second calculation is correct?
2) We know that in GW calculations, the amount of energy correction of the conduction band is higher than that of the valence band. Does this also apply to the stretching of the bands, that is, the stretching of the conduction band should be greater than the stretching of the valence band? Because in my calculations Mv=1.028 is obtained more than Mc=0.908.
Thanks and Regards,
Mitra Helmi