EPW Forum

It is our pleasure to announce the " 2026 School on Electron-Phonon Physics and Many-body Perturbation Theory " which will be held from June 15 to 21 at ICTP in Trieste, Italy. This is an advanced school on first-principles methods for electron-phonon physics and excited-state phenomena, featuring ...

We are pleased to announce that on Sunday, March 15, 2026 we will hold a one-day short course on Electron-phonon physics from first principles: Theory and computational tools under the auspices of the Division of Computational Physics (DCOMP) at 2026 APS Global Physics Summit . To register , please ...

Hello Yujia,

I see, you are using PAW pseudopotential; Can you use ONCV/NC pseudopotential instead of PAW?

Best,
Sabya.

Hi,

Please use V6.0 of EPW (with QE 7.5). This new version outputs the real, imaginary, and the absolute el-ph matrix elements.

Best,
Sabya.

Hello Yujia,

Did you run everything including phonon calculations using QE7.5 or you reused the output from QE7.3? I did not see a phonon calculation in your v6.0 folder.

Best regards,
Sabya.

Hi, I see you have two projections "proj(1): C:sp3" and again the same as proj(2). You don't need that. Here you are projecting the Wannier orbitals on Carbon atom species; so just one "proj(1): C:sp3" is good. That would still mean you have two sp3 orbital projections on two C atoms, leading to a ...

Hi Tong, By looking at your error, most likely you have some missing files in your save folder (a missing dvscf or pattern file). Please check if your ph calculations finished properly. If you still have this error, please attach the full input and output files. Also, let us know the version of QE ...

The EPW Collaboration is pleased to announce a tutorial on "Introduction to EPWpy and MATCSSI," which will be held on November 19, 2025, as part of the MATCSSI Training Series hosted in collaboration with the Texas Advanced Computing Center (TACC). This tutorial will introduce participants to the ...

Dear Topgun,

Yes, you can register for MATCSSI portal if you have a TACC account. You can follow this link "https://tacc.utexas.edu/use-tacc/getting-started/" to getting started with the creation of a TACC account.

Best regards,
Sabya.

Hi Apricity, I see that in the output epw writes " Fermi energy coarse grid = -0.648629 eV". Which means this is the Fermi-level obtained after the NSCF calculation. The reason is that in nscf calculation you have used "smearing = mv" which results in Fermi-level being dependent on your "degauss ...