electron-phonon coupling at Gamma point

Theory Electron-phonon coupling
1

Dear all

I have a simple question about the electron-phonon coupling at Gamma point.
In inhomogeneous systems, for example layered materials, the phonon frequencies and
the electron-phonon coupling at Gamma depend from the direction where they are calculated.

How this direction is decided in EPW?

best
Claudio Attaccalite

2

Dear Claudio,

Sorry for the very late reply.

Exactly at \Gamma, its not decided. The code returns the value of \omega and g without the non-analytical part (exactly what you get from a direct DFPT calculation at \Gamma).

For info, the tolerance on "exactly \Gamma" is 1E-8 in crystal unit.

Hope this helps,
Best,
Samuel