[QE-users] mechanical stability under pressure from phonons

[Paolo Giannozzi]

What I understand from Sec. II.B.4 is that both phonons and elastic
constants computed at constant V, corresponding to an external pressure P,
do not need any pressure correction to be added to stability conditions.

Paolo

On Tue, Jan 12, 2021 at 9:46 AM Uri Argaman <argamanu at post.bgu.ac.il> wrote:

> Thank you very much for your answer Prof. Marzari
>
> However, I still do not understand something. Elastic constants are
> equivalent to phonons in the long-wavelength limit. Thus, if the stability
> condition using elastic constants have explicitly the pressure, also the
> stability condition using phonons should have  explicitly the pressure. Is
> the pressure cancelled out in some way?
> I do not understand it from Grimvall and I do not find any citation on
> this matter.
>
> Uri Argaman
> Ben-Gurion University
> _______________________________________________
> Quantum ESPRESSO is supported by MaX (www.max-centre.eu)
> users mailing list users at lists.quantum-espresso.org
> https://lists.quantum-espresso.org/mailman/listinfo/users



-- 
Paolo Giannozzi, Dip. Scienze Matematiche Informatiche e Fisiche,
Univ. Udine, via delle Scienze 206, 33100 Udine, Italy
Phone +39-0432-558216, fax +39-0432-558222
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.quantum-espresso.org/pipermail/users/attachments/20210112/d6ed1378/attachment.html>