[Pw_forum] problem with symmetry recognition

[Stefano de Gironcoli]

If the symmetry is recognized vc-relax should keep it
if it is not there vc-relax cannot produce it unless the minimum the 
system converges to has that symmetry.
there  are codes (I recently discovered GULP) that can accept input 
structure defined by the positions of the irreducible atoms + space 
group definition...
pw.x does not have this capabiloity but if you generate the full list of 
coordinates with one of such codes then pw.x should be able to recognize 
the symmetry and keep it during relaxation.

stefano
-
Stefano de Gironcoli - SISSA and DEMOCRITOS





On 07/10/2011 09:09 PM, giuseppe.mattioli at mlib.ism.cnr.it wrote:
> Dear all
> I was thinking again about keeping the space group symmetry fixed
> along a vc-relax calculation. Actually, I did not directly ask my main
> question...:-) Is there a way to put the above constraint which I am
> not aware of?
> Yours
>
> Giuseppe
>
> ISM-CNR
> Italy
>