[Wien] combined effective mass

[Oleg Rubel]

In addition to the resources that Gavin sent, the values you quoted are conductivity m*, which is not the same as DOS m* (the formulas are in the paper). The average DOS m* should be available in one of the MSTAR output files. I would not simply combine DOS of bands without taking into account their energy separation and temperature. Combining the contributions is reasonable for degenerate bands, such as the heavy-hole and light-hole bands at the valence-band maximum. The split-off band is further down in energy.

I hope it will help,
Oleg

> -----Original Message-----
> From: Wien <wien-bounces at zeus.theochem.tuwien.ac.at> On Behalf Of
> Gavin Abo
> Sent: Friday, September 11, 2026 8:55 AM
> To: wien at zeus.theochem.tuwien.ac.at
> Subject: Re: [Wien] combined effective mass
> 
>   Caution: External email.
> 
> Sorry, I currently don't know, but wondering if you are perhaps working with
> equation 11 in [1] or equation A-21 in [2] containing mHH*, mLH*, and
> mSO*?
> 
> [1] https://doi.org/10.1038/s41598-025-91800-8
> <https://doi.org/10.1038/s41598-025-91800-8>
> [2] https://scispace.com/pdf/the-theoretical-and-experimental-study-of-the-
> temperature-26z6ivmbco.pdf <https://scispace.com/pdf/the-theoretical-
> and-experimental-study-of-the-temperature-26z6ivmbco.pdf>
> 
> Kind Regards,
> 
> Gavin
> WIEN2k user
> 
> On 9/11/2026 1:24 AM, uchit chaudhary wrote:
> 
> 
> 	Dear Experts,
> 
> 	I am using the WIEN2k mstar code with spin–orbit coupling (SOC) to
> calculate the effective masses at the valence-band maximum (VBM) and
> conduction-band minimum (CBM).
> 
> 	For my FCC cubic material, the VBM is located at Gamma, while the
> CBM is located at X. From the minv_c-up.dat output, I obtained the following
> effective masses.
> 
> 	For the VBM at Gamma (k-point 47), I identified three pairs of bands
> corresponding approximately to the heavy-hole (HH), light-hole (LH), and
> split-off (SO) bands:
> 
> 	*	Bands 48–47: 1/0.4831 = 2.0699 m0 — HH
> 	*	Bands 46–45: 1/4.875 = 0.2051 m0 — LH
> 	*	Bands 44–43: 1/1.716 = 0.5827 m0 — SO
> 
> 	For the CBM at X (k-point 101), I obtained:
> 
> 	*	Bands 50–49: 1/1.309 = 0.7639 m0
> 
> 	My main question is how I should calculate the combined density-of-
> states (DOS) effective mass for the VBM and CBM in this situation.
> 
> 	In particular, I am unsure how the SOC-related band pairs should be
> counted. Since the SOC calculation produces two bands with very
> similar/equal effective masses, should these be treated as a spin degeneracy of
> 2, or should each HH, LH, and SO effective mass be counted only once when
> calculating the combined DOS effective mass?
> 
> 	 Based on my values above, what would be the correct combined DOS
> effective mass for the VBM and CBM?
> 
> 	I would greatly appreciate your guidance on the correct procedure.
> 
> 	Thank you for your help.
> 
> 	Thank you for your guidance.
> 
> 	Best regards,
> 	wien2k user