about NBANDS problem

Queries about input and output files, running specific calculations, etc.


Moderators: Global Moderator, Moderator

Post Reply
Message
Author
chengjun

about NBANDS problem

#1 Post by chengjun » Sat Jan 17, 2009 3:29 pm

hi everyone,
In the VASP manual, it said you should increase the NBANDS in the INCAR file when you deal with transition metal.

so, when i calculate the band stucture of Sc doped SrTiO3 (2x2x2supercell with one doping atom at Ti position), I increased the NBANDS=240 value like manual said.

But after calculating, I find the number of bands each k (also NBANDS=256 in OUTCAR) is a little bit larger than NBANDS I set.

Can anyone explain it for me? thanks in advance.
Last edited by chengjun on Sat Jan 17, 2009 3:29 pm, edited 1 time in total.

Danny
Full Member
Full Member
Posts: 201
Joined: Thu Nov 02, 2006 4:35 pm
License Nr.: 5-532
Location: Ghent, Belgium
Contact:

about NBANDS problem

#2 Post by Danny » Sun Jan 18, 2009 5:33 pm

The NBANDS has to be a multiple of your CPU-cores(in your case you ran 32 CPU cores (if I calculated correctly))

This, you also have to think of when you want to use the WAVECAR file in the future,
1) set the NBANDS to that of the calculation that generated the WAVECAR
2) only run on a number of cpu-cores such that NBANDS is a multiple of this.

Danny
Last edited by Danny on Sun Jan 18, 2009 5:33 pm, edited 1 time in total.

Post Reply