[Pw_forum] K_points

[Giuseppe Mattioli]

Dear Khadije Khalili
A non-periodic object is not, in principle, characterised by dispersed electronic states in the reciprocal space. Dispersion arises sometimes if your 
molecule interacts strongly with its periodically repeated images, but it has to be considered as a spurious effect of a too small supercell. So put 
your molecule in a satisfactorily large cell and use Gamma only to sample the Brillouin zone.

HTH

Giuseppe
  

On Sunday 16 June 2013 18:20:51 raha khalili wrote:
> Dear Users
> 
> I want to relax a molecule in X-Y plane. What is the best k-point for my
> caculation? What the diference between 2 2 1 1 1 0 and 2 2 1 1 1 1?
> 
> Best Wishes


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   Giuseppe Mattioli                            
   CNR - ISTITUTO DI STRUTTURA DELLA MATERIA   
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