<div dir="ltr"><div>The Al defect in SiO2 has a wrong structure with GGA ...</div><div>Sorry for the wrong subject of my original message.</div><div><br></div><div>Paolo<br></div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Wed, May 6, 2020 at 8:54 PM Layla Martin-Samos <<a href="mailto:lmartinsamos@gmail.com">lmartinsamos@gmail.com</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir="ltr"><div>Thank you Nicola, I always think at sp materials, and forget partially filled d bands ... :D! Thank you for the reference.</div><div><br></div><div>cheers</div><div><br></div><div>Layla<br> </div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">Le mer. 6 mai 2020 à 20:06, Nicola Marzari <<a href="mailto:nicola.marzari@epfl.ch" target="_blank">nicola.marzari@epfl.ch</a>> a écrit :<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><br>
<br>
Well, transition-metal oxides can be a good example - see the work here <br>
from the "U" gang for the phonons in CoO - major differences:<br>
<a href="https://arxiv.org/abs/1910.06195" rel="noreferrer" target="_blank">https://arxiv.org/abs/1910.06195</a> (paper is now published in PRB).<br>
<br>
So, the question is when is EXX better than Hubbard, and one would want <br>
DFPT+EXX rather than DFPT+U (that is available)? I think for localized <br>
d/f orbitals the Hubbard approach is nicer, much less expensive, and <br>
tuned to the actual system studied.<br>
<br>
In something where self-interaciton is less well identifiable (say, an <br>
oxidized thiophene where the hole is difficult to describe), well, one <br>
could not use U and would hope that EXX helps.<br>
<br>
nicola<br>
<br>
<br>
<br>
On 06/05/2020 19:57, Layla Martin-Samos wrote:<br>
> I am not aware of any case (material, molecule, ...) in which the <br>
> vibrational spectra would have been so crappy with standard functionals <br>
> (no fock) that could justify the burden of phonons with EXX <br>
> (calculation, implementation etc...). Someone is aware of some <br>
> application of that kind? (or maybe the question was on TDDFPT?)<br>
> <br>
> Layla<br>
> <br>
> Le mer. 6 mai 2020 à 18:58, Paolo Giannozzi <<a href="mailto:p.giannozzi@gmail.com" target="_blank">p.giannozzi@gmail.com</a> <br>
> <mailto:<a href="mailto:p.giannozzi@gmail.com" target="_blank">p.giannozzi@gmail.com</a>>> a écrit :<br>
> <br>
> Somebodty asked me the following question. Any comments (opther than<br>
> "it will be horribly slow")?<br>
> <br>
> > Do you know if anyone working on implementing DFPT + hybrid<br>
> functionals ?<br>
> <br>
> Paolo<br>
> <br>
> <br>
> <br>
> -- <br>
> Paolo Giannozzi, Dip. Scienze Matematiche Informatiche e Fisiche,<br>
> Univ. Udine, via delle Scienze 208, 33100 Udine, Italy<br>
> Phone +39-0432-558216, fax +39-0432-558222<br>
> <br>
> _______________________________________________<br>
> developers mailing list<br>
> <a href="mailto:developers@lists.quantum-espresso.org" target="_blank">developers@lists.quantum-espresso.org</a><br>
> <mailto:<a href="mailto:developers@lists.quantum-espresso.org" target="_blank">developers@lists.quantum-espresso.org</a>><br>
> <a href="https://lists.quantum-espresso.org/mailman/listinfo/developers" rel="noreferrer" target="_blank">https://lists.quantum-espresso.org/mailman/listinfo/developers</a><br>
> <br>
> <br>
> _______________________________________________<br>
> developers mailing list<br>
> <a href="mailto:developers@lists.quantum-espresso.org" target="_blank">developers@lists.quantum-espresso.org</a><br>
> <a href="https://lists.quantum-espresso.org/mailman/listinfo/developers" rel="noreferrer" target="_blank">https://lists.quantum-espresso.org/mailman/listinfo/developers</a><br>
> <br>
<br>
<br>
-- <br>
----------------------------------------------------------------------<br>
Prof Nicola Marzari, Chair of Theory and Simulation of Materials, EPFL<br>
Director, National Centre for Competence in Research NCCR MARVEL, EPFL<br>
<a href="http://theossrv1.epfl.ch/Main/Contact" rel="noreferrer" target="_blank">http://theossrv1.epfl.ch/Main/Contact</a> <a href="http://nccr-marvel.ch/en/project" rel="noreferrer" target="_blank">http://nccr-marvel.ch/en/project</a><br>
</blockquote></div>
_______________________________________________<br>
developers mailing list<br>
<a href="mailto:developers@lists.quantum-espresso.org" target="_blank">developers@lists.quantum-espresso.org</a><br>
<a href="https://lists.quantum-espresso.org/mailman/listinfo/developers" rel="noreferrer" target="_blank">https://lists.quantum-espresso.org/mailman/listinfo/developers</a><br>
</blockquote></div><br clear="all"><br>-- <br><div dir="ltr" class="gmail_signature"><div dir="ltr"><div><div dir="ltr"><div>Paolo Giannozzi, Dip. Scienze Matematiche Informatiche e Fisiche,<br>Univ. Udine, via delle Scienze 208, 33100 Udine, Italy<br>Phone +39-0432-558216, fax +39-0432-558222<br><br></div></div></div></div></div>