[Wien] Deviation of elastic constants from reference values

[Lyudmila Dobysheva]

On 11.01.2015 17:23, Muhammad Sajjad wrote:
> Although change of XC potential provides C44 values
> very close to that of experimental study but other elastic constants
> C11, C12 deviates widely.

>  I got negative values.

Negative because you took too small number of k-points

> What number of k-points i should select then?
Recently I did an fcc Al calculation, it demanded 30-40 000 Nk points in 
the BZ for good values. And do pay attention that you are in the minimum 
of energy in all the three calculations.

As Prof Blaha wrote: spin-polarization for Fe.

Best wishes
   Lyudmila Dobysheva
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