[Pw_forum] Symmetry problem

[Yan]

On 2009/03/22 Sunday 09:58:46 孙阳 wrote:
> By looking at the CELL_PARAMETER, we see that the crystal loose the
> symmetry of orthorhombic but simply triclinic.
>
> Can we do VC-relax by keeping the previous symmetry?
maybe the variable 'cell_dofree'  in namelist 'CELL' is something your are 
looking for. However, this option is not a robust enough, and it is not 
recommend to use it.

you can try to restart with the cell parameters you got and ignore the 
divergence of  symmetry. 

>CELL_PARAMETERS (alat)
>   0.496579626   0.283698921  -0.001038829
>  -0.496579626   0.283698921  -0.001038829
>   0.000000000  -0.002166536   0.600253523

CELL_PARAMETERS (alat)
   0.496579626   0.283698921   [0]
  -0.496579626   0.283698921   [0]
   0.000000000  [0]   0.600253523

this is only a suggestion, I didn't try it out, so may be incorrect.
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