[QE-users] Disable final scf cycle in vc-relax

[Bidault, Xavier]

My guess is that the cutoff is too short. If the volume has changed a lot after the relaxation, the initial number of planewaves no more fits that volume. I think the final scf cycle is meant to assess this, in order to check if the cutoff (and the planewaves number related to this volume) if still valid and relevant.

Xavier Bidault

________________________________
From: users <users-bounces at lists.quantum-espresso.org> on behalf of Paolo Giannozzi <p.giannozzi at gmail.com>
Sent: Wednesday, February 5, 2020 10:22 AM
To: Quantum ESPRESSO users Forum <users at lists.quantum-espresso.org>
Subject: Re: [QE-users] Disable final scf cycle in vc-relax

There is no way to disable the last scf step from input. You may easily do that by modifying PW/src/move_ions.f90: change lines 153 and 160 to
                 ions_status = 0
and the code will not execute the last step (neither the one with nonzero magnetization nor the one with the final cell).
Note however that you cannot run a non-scf calculation starting from the data of the variable-cell optimization and that convergence trouble in the last step won't go away in a new calculation.

Paolo



On Wed, Feb 5, 2020 at 3:56 PM Malte Sachs <malte.sachs at chemie.uni-marburg.de<mailto:malte.sachs at chemie.uni-marburg.de>> wrote:
Dear all,

I often have scf-convergence problems at the final scf cycle of a
vc-relax calculation. Is there an easy way to disable this step of the
calculation (e.g. a hidden keyword) to save some computer time?

Thank you and best regards,

Malte Sachs

--
Malte Sachs
Anorganische Chemie, Fluorchemie
Philipps-Universität Marburg
Hans-Meerwein-Straße 4
35032 Marburg (Paketpost: 35043 Marburg)
Tel.: +49 (0)6421 28 - 25 68 0
http://www.uni-marburg.de/fb15/ag-kraus/


_______________________________________________
Quantum ESPRESSO is supported by MaX (www.max-centre.eu/quantum-espresso<http://www.max-centre.eu/quantum-espresso>)
users mailing list users at lists.quantum-espresso.org<mailto: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 208, 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/20200205/14a79a58/attachment.html>