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[ERROR]Fractional e/h occupations found

Posted: Mon Jan 16, 2012 12:10 pm
by wlyim
Dear all,

My computed system is metallic by DFT and becomes semiconducting after GW correction. But even I applied the scissor operator by setting the KfnQP_E parameter in BSE calculation, the job crashed because of the fractional e/h occupations. I guess that the program still took the original occupations by pure DFT. Am I right? And how can I fix this problem?

Best regards,
William

Re: [ERROR]Fractional e/h occupations found

Posted: Fri Feb 24, 2012 12:47 am
by claudio
Dear William

you can use the Bethe-Salpeter without the Tamm-Dancoff approximation
that should work with any occupation.
See the tutorial on SiH4

http://www.yambo-code.org/tutorials/SiH4/index.php

best regards
Claudio