[Pw_forum] change of crystal symmetry during vc-relax calculations with pressure

[Paolo Giannozzi]

On Fri, 2013-06-14 at 13:09 +0000, saqib javed wrote:

> Furthermore the initial symmetry for both cases as written
> at start of output reads the same
> 
> 2 Sym. Op. (with inversion)

that is: Identity + Inversion. So these two symmetries will be kept
during optimization, because forces and stresses are symmetrized.
All others symmetries may be broken by numerical noise (but if the
system doesn't want to distort, it will stay close to a more
symmetric state)

P.

-- 
 Paolo Giannozzi, Dept. Chemistry&Physics&Environment, 
 Univ. Udine, via delle Scienze 208, 33100 Udine, Italy
 Phone +39-0432-558216, fax +39-0432-558222