[Wien] Effective mass

[Rubel, Oleg]

Are you referring to the transport-equivalent effective mass for degenerate bands, perhaps in the sense of Sec. IIIB of this paper on the ABINIT implementation: https://arxiv.org/abs/1708.05890
mstar uses degenerate perturbation theory and can obtain masses associated with, for example, heavy-hole and light-hole branches. It also reports a conductivity-related mass via Eq. (9) in our paper: https://rubel75.github.io/publications/2021/Rubel-CPC_261_2021.pdf
However, these quantities are still associated with the resolved degenerate manifold, so I am not sure we went as far as the ABINIT implementation in defining a transport-equivalent effective mass for the full degenerate extremum.

Oleg
> -----Original Message-----
> From: Wien <wien-bounces at zeus.theochem.tuwien.ac.at> On Behalf Of
> Laurence Marks
> Sent: Wednesday, April 8, 2026 6:11 PM
> To: A Mailing list for WIEN2k users <wien at zeus.theochem.tuwien.ac.at>
> Subject: Re: [Wien] Effective mass
> 
>   Caution: External email.
> ..not the decomposition by band and kpoint...
> 
> ---
> Emeritus Professor Laurence Marks (Laurie) www.numis.northwestern.edu
> <http://www.numis.northwestern.edu>
> https://scholar.google.com/citations?user=zmHhI9gAAAAJ&hl=en
> "Research is to see what everybody else has seen, and to think what nobody
> else has thought" Albert Szent-Györgyi
> 
> On Wed, Apr 8, 2026, 17:05 Laurence Marks <laurence.marks at gmail.com
> <mailto:laurence.marks at gmail.com> > wrote:
> 
> 
> 	It gives them for each band. The conventional definition of electron &
> hole effective masses are at the VB and CB edges, which is what I want, not the
> decomposition by band.