The ABINIT Users Mailing List ( CLOSED )

["PRASENJIT GHOSH" <prasenjit@jncasr.ac.in>]

For semiconductors and insulators:

(1) If you donot need the bands above Fermi level, nband=Total no. of
electrons in the system/2;

(2) If u need the unoccupied bands, for eg. if u want to plot band
structure, then nband=(Total no. of electrons in the system/2)+x, where
'x' is the number of extra bands you need. Typically for band structure
calculations x=7-10.

For metals:

nband= (Total no. of electrons in the system/2) + x,
where x is the no. of extra bands u should add because the energy bands
cross at Fermi energy. Typically x=20% of no. of electrons/2.
However the best thing is to check the convergence of total energy of the
system w.r.t. nbands.

With regards,
Prasenjit.


On Tue, July 10, 2007 16:13, xd0533@163.com said:
> When I calculate energy band,I need set nband parameter.What is the
> principle of setting nband? Thanks a lot!
> Best Wishes!
> xiang
>


PRASENJIT GHOSH,
Ph. D STUDENT,
THEORETICAL SCIENCES UNIT,
JAWAHARLAL NEHRU CENTRE,
JAKKUR P. O.,
BANGALORE - 560064,
INDIA.

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