EPW Forum

Hi Giuseppe, The Fermi-level is found by using a bisection method (iterative) since its a root-finding problem. However, there is an upper-bound to the number of iterations. That means, once the max number of iterations is reached and the relative error (which is 1e-5) between previous and current ...

Hi,

You need to delete the restart files (restart.fmt, F*) present in your directory when you change the fine-grid of your calculation.

Best regards,
Sabya.

Hi Can you kindly post the system size (k-grid, q-grid, and number of bands (nbndsub)) along with parallelization setting used for running epw.x? Also, can you post the output files? The possible reason for such drop in performance can be the compilation of epw. It may be useful to try compiling epw ...

Hello, There is an ongoing effort to make EPW work with DFT+U/DFPT+U. Hopefully, in EPW v6.0 (to be released next year summer) we will have DFT+U/DFPT+U. Although in the current version of EPW one cannot add the effect of U to phonons and electron-phonon matrix elements, correction to electronic ...

EPW version 5.9 has been released. You can read more regarding the release on the EPW website: https://docs.epw-code.org/doc/Releases.html. The EPW v.5.9 has a known issue regarding compilation when downloaded with QE v.7.4 Release. We reccommend downloading EPW v5.9 from the EPW website which has ...

Hi Donglin, There are multiple codes which can produce the uniform grid in the full Brillouin zone. The easiest method is to use the perl code below (Part of Wannier90 distribution kmesh.pl). To run the code below and generate a 6 6 6 k-grid -> perl kmesh.pl 6 6 6 Best regards, Sabya [#!/usr/bin ...

Hi,

Can you try increasing the fine-grid (nkf and nqf)? If that does not work can you attach your input and output files?

Best regards,
Sabya.

Hi Jianguo,

I think the problem comes from the fsthick. Increase the fsthick size or use etf_mem=0 in your epw input file. If that does not help, please check the q-point path that it does not have any discontinuity.

Best regards,
Sabya.

Hi,

Yes, the PAO is not yet implemented inside the external Wannier library in QE. Hence, the PAO at the moment cannot be used with EPW (as of EPW 5.9). Hopefully, it will become part of the QE soon.

Best regards,
Sabya.

Hi

EPW is not tested for such large system sizes.
For QE related questions please use QE users forum (https://www.quantum-espresso.org/users-forum/).

Best regards,
Sabya.