[Pw_forum] nondegenerate electrons in DFT.

[Jiayu Dai]

> 
> Correct - you would use Fermi-Dirac for the electronic occupations, and 
> include
> enough bands to make sure the the highest bands are almost empty.
> 
Thanks a lot. Therefore, we can deal with the nondegenerate electrons using this
way. However, i think the convergence and the computational speed should be a
problem in this case. 

> This is the canonical extension to DFT according to Mermin (look at his 
> Phys Rev papers
> from the late 60s) - note that the true xc functional would be 
> temperature-dependent, but
> you would use a 0 temperature one. There might be early work (Singwi ?) 
> on the matter.
>
About the effect of xc functional in MD, there is a work recently talking about
it(High Energy Density Physics,5,2009,74). And the found small influence.
Therefore, i think we can use a zero temperature xc functional here.

Thanks.

Jiayu




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Jiayu Dai
Department of Physics
National University of Defense Technology, 
Changsha, 410073, P R China
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