[Pw_forum] Band structure calculation HOWTO

[Paolo Giannozzi]

On Apr 9, 2008, at 15:12 , Janos Kiss wrote:

> I have found a nice tutorial on the band structure calculation of  
> bulk Si:
> http://people.sissa.it/~degironc/QE-Tutorial/tutorial_pwscf_ex.pdf
> http://people.sissa.it/~degironc/QE-Tutorial/examples_pwscf_ex.tgz

nice but very old. There is a newer version which for obscure reasons
never percolated to the web site.

> I'm just wondering where this discrepancy is coming from. Did i  
> miscompile
> the code, or eventually the tutorial was done by mistake with
> different settings/pseudopotential?

different pseudopotentials is the likely answer. Absolute values of  
Kohn-Sham
states vary with the pseudopotentials

> In what extent will be affected the band structure by the smearing  
> scheme if
> eventually the system changes from the metallic state to a  
> semiconductor by
> some adsorbates/surface defects?


if the smearing is small wrt the gap, results will be affected very  
little

Paolo
---
Paolo Giannozzi, Dept of Physics, University of Udine
via delle Scienze 208, 33100 Udine, Italy
Phone +39-0432-558216, fax +39-0432-558222