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

> from what I have read to get the the number of bands (nbands) we multiply
> the
> occupancy with the total number of electrons, that is  2*total number of
> electrons. I am calculating using an insulating structure with a total of
> 20
> valence electrons, ideally then I should have 40 bands but when I input
> this
> number of bands the code complains. Using the automatic generation of
> bands
> occopt gives the double the number i.e 80. Why is this so?
>

This is strange.....shouldn't it be 0.5* total no. of electrons (each band
can accommodate two electrons). Therefore if your system is insulating
with 20 valence electrons, in principle 10 bands should be sufficient if
you just want to find the ground state geometry.

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

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