On Fri, 2013-06-14 at 13:09 +, 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 stres
in
> my reasoning.
>
> cheers
> Saqib
> NCP, Pakistan
>
>
> > From: paolo.giannozzi at uniud.it
> > To: pw_forum at pwscf.org
> > Date: Fri, 14 Jun 2013 12:34:57 +0200
>
> > Subject: Re: [Pw_forum] change of crystal symmetry during vc-relax
> cal
in my reasoning.
cheersSaqibNCP, Pakistan
> From: paolo.giannozzi at uniud.it
> To: pw_forum at pwscf.org
> Date: Fri, 14 Jun 2013 12:34:57 +0200
> Subject: Re: [Pw_forum] change of crystal symmetry during vc-relax
> calculations with pressure
>
> On Fri, 2013-06-14 at 09:13
.
cheersSaqibNCP, Pakistan
> From: paolo.giannozzi at uniud.it
> To: pw_forum at pwscf.org
> Date: Fri, 14 Jun 2013 12:34:57 +0200
> Subject: Re: [Pw_forum] change of crystal symmetry during vc-relax
> calculations with pressure
>
> On Fri, 2013-06-14 at 09:13 +, saqib javed wr
On Fri, 2013-06-14 at 09:13 +, saqib javed wrote:
> i started with tetragonal structure (ibrav=6) so i would have imagined
> that a=b would have been enforced by the code in case symmetry is
> conserved during optimization ...
symmetry IS conserved during optimization, apart from unfortunate
On Fri, 2013-06-14 at 07:18 +, saqib javed wrote:
> Can vc-relaxation at a given pressure with bfgs method allows for
> change of crystal symmetry ??
no, but only the symmetry as found by the code is conserved;
"accidental" symmetries, e.g. lattice vectors a and b having
equal length but no
Date: Fri, 14 Jun 2013 10:43:36 +0200
> Subject: Re: [Pw_forum] change of crystal symmetry during vc-relax
> calculations with pressure
>
> On Fri, 2013-06-14 at 07:18 +, saqib javed wrote:
>
> > Can vc-relaxation at a given pressure with bfgs method allows for
> > ch
Dear PWSCF users,
I have a question regarding vc-relaxation with bfgs. I am trying to optimize
lattice parameters and atomic positions of unit cell at high pressures. while
initial symmetry of unit cell is tetragonal (a=b), the optimized cell
parameters at P=25 GPa seems to be in orthorhombic s
