[Pw_forum] Imposed symmetry

[Gabriele Sclauzero]

Green Power wrote:
> Dear PWscf users,
> I wonder if PWscf can deal with imposed symmetry for structural 
> relaxation calculations. If so, dose the imposed symmetry speed up the 
> calculations? Thanks in advance.

The symmetry is determined at the beginning of the run and depends on the bravais lattice, 
atomic positions and maybe other stuff (like starting magnetization for noncolinear 
calculations with SO).
Everything is symmetrizing with this initial symmetry which holds during all the relaxation.
You may want to break symmetry, rather than imposing it, when doing structural relaxations 
in order not to be confined in a subspace of configurations.

If you want to impose constraints, well, that's another story...

GS


> 
> Tian
> Georgetown University
> Washington DC 20057
>  
> 
> 
> ------------------------------------------------------------------------
> 
> _______________________________________________
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://www.democritos.it/mailman/listinfo/pw_forum

-- 


o ------------------------------------------------ o
| Gabriele Sclauzero, PhD Student                  |
| c/o:   SISSA & CNR-INFM Democritos,              |
|        via Beirut 2-4, 34014 Trieste (Italy)     |
| email: sclauzer at sissa.it                         |
| phone: +39 040 3787 511                          |
| skype: gurlonotturno                             |
o ------------------------------------------------ o