[Pw_forum] Phonon calculation at high pressure

Bipul Rakshit bipulrr at gmail.com
Wed Aug 27 14:24:26 CEST 2008


Hello Eyvaz Isaev,
Thanks for your kind attention and your reply.
Just one doubt, you said *"decrease the lattice parameter"*, means keeping
in scf (or relax run ) from the initial ScAs (B1) structure or considering
ScAs (B2) structure?

regards

On Wed, Aug 27, 2008 at 2:07 PM, Eyvaz Isaev <eyvaz_isaev at yahoo.com> wrote:

> Dear Bipul,
>
> --- On Wed, 8/27/08, Bipul Rakshit <bipulrr at gmail.com> wrote:
>
> >
> > But for B2 structure I am getting many -ve frequencies.
> > Although ScAs (B2) structure is stable at some high
> > pressure, so do i have to set some pressure
> > in the system and then I have to do the phonon
> > calculation?
>
> Yes, this is the correct way. Just set up tstress=.true. and tprnfor=.true.
> in order to monitor what is pressure in your high pressure ScAs phase.
>
> >
> > In simple words, how can i do the phonon calculation for ScAs (B2)
> structure which is structure at high pressure?
> >
>
> In simple words, decrease the lattice parameter and see what say above
> mentioned keywords about pressure, then continue your phonon calculations.
>
> Bests,
> Eyvaz.
> >
> > --
> > Bipul Rakshit
> > PhD Student,
> > Barkatullah University,
> > Bhopal 462026,
> > MP, India
> > _______________________________________________
>
>
> -------------------------------------------------------------------
> Prof. Eyvaz Isaev,
> Theoretical Physics Department, Moscow State Institute of Steel & Alloys,
> Russia,
> Department of Physics, Chemistry, and Biology (IFM), Linkoping University,
> Sweden
> Condensed Matter Theory Group, Uppsala University, Sweden
> Eyvaz.Isaev at fysik.uu.se, isaev at ifm.liu.se, eyvaz_isaev at yahoo.com
> > Pw_forum mailing list
> > Pw_forum at pwscf.org
> > http://www.democritos.it/mailman/listinfo/pw_forum
>
>
>
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-- 
Bipul Rakshit
PhD Student,
Barkatullah University,
Bhopal 462026,
MP, India
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