Hi,
I am calculating band structure and fermi surfaces for a narrow-gap semiconductor using LDA, full relativistic, NC PPs.
When I plot band structure I see a band gap of about 0.04eV, but When I want to plot Fermi Surfaces using Xcrysden by .bxsf file, I saw some overlap between Valance and Conduction band, i.e. there is some contribution from valance bands at Fermi level.
Could you please guide me what is the problem with that?
I followed the instructions written for "prtfsurf" (iscf2:-3 ,prtfsurf2 1, defined suitable nbnd and a really dense kpoint grid with zero shift) for plotting Fermi surfaces and used my optimized parameters and atomic positions:
iscf2 -3
getden2 -1
kptopt2 1
nshiftk2 1
shiftk2 0.0 0.0 0.0
ngkpt2 50 50 50
nband2 40
tolwfr2 1.0d-18
enunit2 1
prtfsurf2 1
Then, my next question is that I want to run my calculations for fermi surfaces using "Tetrahedra Method". I'd appreciate if you could guide me how to do that.
Thank you so much!
Best,
Shima
Problem with Plotting Fermi Surfaces
Moderators: MMNSchmitt, gonze