[Pw_forum] About Electron-Phonon Coupling matrix element in QE4.2.1

[Eyvaz Isaev]

----- Original Message ----
From: 程迎春 <yccheng.nju at gmail.com>
 
>>In addition, I guess  " 0.318816E-08  0.318816E-08  0.318816E-08"
>>are the elctron-phonon coupling matrix elements.
>
> No, they are frequencies in Ry.

Please see previous mail correction to this answer (Ry^2, not Ry).

>
> I am not sure about they are frequencies

You are almost right, see above, as I missed (^2).

I have just checked again 

13.6058*8065.5*sqrt(0.185711)/sqrt(10^5) = 149.54579 

In my calculations : 13.6058*8065.5*sqrt(0.185683)/sqrt(10^5) = 149.5345 
(149.534340 in dyn3-file)

>  the value in second line are not EPC matrix elements, where can I find them?

I am not sure, you can find them printed, please have a look at elphon.f90 file 
(elphel subroutine inside), but EPC constant, lambda, can be found in 
lambda-file.

Bests,
Eyvaz.
 
-------------------------------------------------------------------
> Prof. Eyvaz Isaev,
> Department of Physics, Chemistry, and Biology (IFM), Linkoping University,
> Sweden
>
> Theoretical Physics Department, Moscow State Institute of Steel & Alloys,
> Russia,
>
> isaev at ifm.liu.se, eyvaz_isaev at yahoo.com
>