[Wien] k point

[Stefaan Cottenier]

> Why the number of the k points in the case of super-cell becomes
> leeser than the k point in the case of the bulk samples.
>
> I have read that the calculations for the unit cell is obtained with
> 35 k-points, while for the supercell with vacancies the calculations
> is obtained with only 2 k-points. It would be reasonable to compare
> the results if all the calculations are converged with the number of
> k-points.

The larger the unit cell the direct lattice, the smaller the unit cell  
of the reciprocal lattice (Brillouin zone). Hence, the fewer k-points  
fall inside the first Brillouin zone if the density of the k-mesh  
(which determines the accuracy of the calculation) is kept constant.

Stefaan


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