<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<style type="text/css" style="display:none;"> P {margin-top:0;margin-bottom:0;} </style>
</head>
<body dir="ltr">
<div style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
Dear Professors Paulatto, Gionazzi and Marzari,</div>
<div style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<br>
</div>
<div style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
Thank you for the information. I am aware of the EPW code. I have used it myself in a recent publication.</div>
<div style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
I have heard of Perturbo but not of Phoebe or epik.</div>
<div style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
I will have a look at these and choose the most suitable.</div>
<div style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<br>
</div>
<div style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
Regards<br>
</div>
<div style="font-family: Calibri, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);">
<br>
</div>
<div>
<hr tabindex="-1" style="display:inline-block; width:98%">
<div id="divRplyFwdMsg" dir="ltr"><font style="font-size:11pt" face="Calibri, sans-serif" color="#000000"><b>From:</b> users <users-bounces@lists.quantum-espresso.org> on behalf of Nicola Marzari via users <users@lists.quantum-espresso.org><br>
<b>Sent:</b> Monday, December 6, 2021 6:28 AM<br>
<b>To:</b> users@lists.quantum-espresso.org <users@lists.quantum-espresso.org><br>
<b>Subject:</b> Re: [QE-users] Enquiry about electron-phonon calculation</font>
<div> </div>
</div>
<div class="BodyFragment"><font size="2"><span style="font-size:11pt">
<div class="PlainText">On 06/12/2021 08:59, Lorenzo Paulatto wrote:<br>
> Yet it is possible. You need a very goo representation of the Fermi <br>
> surface in order to identify the possible el-ph processes, but such a <br>
> fine grid is not required to have good phonons.<br>
> <br>
> Also note that there are at least two QE packages to do el-ph <br>
> calculation with Wannier interpolation : epik by M Calandra and EPW by F <br>
> Giustino<br>
> <br>
<br>
Thanks Lorenzo - maybe just for completeness I should add the other two <br>
I know of (to 4 altogether - an embarassment of riches...):<br>
<br>
Perturbo: <a href="https://perturbo-code.github.io/">https://perturbo-code.github.io/</a><br>
Phoebe: <a href="https://arxiv.org/abs/2111.14999">https://arxiv.org/abs/2111.14999</a><br>
<br>
Also, I do not think epik is available open-source somewhere, correct?<br>
<br>
nicola<br>
<br>
<br>
> regards<br>
> <br>
> --<br>
> Lorenzo Paulatto - Paris<br>
> On Dec 6 2021, at 3:27 am, Elio Physics <Elio-Physics@live.com> wrote:<br>
> <br>
> Dear all,<br>
> <br>
> As is well known in electron-phonon calculations, one has to do a<br>
> self consistent (scf) calculation over a dense electronic grid<br>
> followed by an scf calculation on a coarse grid.<br>
> The electron phonon calculation is usually performed after<br>
> calculation the vibrational frequencies for each point.<br>
> <br>
> My question is : If we increase the dense grid, Is it possible (Is<br>
> there a way in QE) to compute the el-ph coefficients without<br>
> recomputing the dynamical files (vibrational frequencies), which<br>
> actually depend on the coarse grid. This would save a lot of time.<br>
> <br>
> Thanks in advance<br>
> <br>
> Ellie Moujaes<br>
> Federal Universil of Rondonia<br>
> Brazil<br>
> _______________________________________________<br>
> Quantum ESPRESSO is supported by MaX (<a href="http://www.max-centre.eu">www.max-centre.eu</a>)<br>
> users mailing list users@lists.quantum-espresso.org<br>
> <a href="https://lists.quantum-espresso.org/mailman/listinfo/users">https://lists.quantum-espresso.org/mailman/listinfo/users</a><br>
> <br>
> Sent from Mailspring<br>
> <br>
> _______________________________________________<br>
> Quantum ESPRESSO is supported by MaX (<a href="http://www.max-centre.eu">www.max-centre.eu</a>)<br>
> users mailing list users@lists.quantum-espresso.org<br>
> <a href="https://lists.quantum-espresso.org/mailman/listinfo/users">https://lists.quantum-espresso.org/mailman/listinfo/users</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, SNSF<br>
Head, Laboratory for Materials Simulations, Paul Scherrer Institut<br>
Contact info and websites at <a href="http://theossrv1.epfl.ch/Main/Contact">http://theossrv1.epfl.ch/Main/Contact</a><br>
_______________________________________________<br>
Quantum ESPRESSO is supported by MaX (<a href="http://www.max-centre.eu">www.max-centre.eu</a>)<br>
users mailing list users@lists.quantum-espresso.org<br>
<a href="https://lists.quantum-espresso.org/mailman/listinfo/users">https://lists.quantum-espresso.org/mailman/listinfo/users</a></div>
</span></font></div>
</div>
</body>
</html>