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Smearing problem in qp spectral function!

Posted: Tue Feb 07, 2017 7:42 am
by sitangshu
Dear Sir,

While doing a calculation with Si bulk, I made "occupation" to be a "fixed" in my ground state calculation. I understood that this actually removes the "Warning: Metallic System" note that comes after the yambo calculation. However, when I progress further with this for the qp electron-phonon calculations using elph_qp, the non-zero temperature suffers NAN error.
This however does not come when I change "fixed" to "guassian" with a suitable "degauss"!.
Where I am doing wrong, if you can tell me please...

With regards

Sitangshu

Re: Smearing problem in qp spectral function!

Posted: Tue Feb 07, 2017 9:32 am
by amolina
Dear Sitangshu,
I don't understand very well where it can be the problem. Can you attach a tar file with the QE and yambo input files?

Re: Smearing problem in qp spectral function!

Posted: Tue Feb 07, 2017 9:52 am
by sitangshu
Dear Alejandro,

Here are the files attached...

Regards,
Sitangshu

Re: Smearing problem in qp spectral function!

Posted: Tue Feb 07, 2017 10:09 am
by amolina
Dear Sitangshu,
what I see from the inputs is the runlevel for a GW calculation. I don't think you can set the Bose Temperature in this calculation if you don't have the electron-phonon matrix elements.
Alejandro.

Re: Smearing problem in qp spectral function!

Posted: Tue Feb 07, 2017 11:16 am
by sitangshu
Dear Alejandro,

I think I am not understanding.... Please excuse me. Please tell me where I am wrong..
1. I understand that the current version of Yambo doesn't include Matsubara analysis.
2. The inclusion of temperature comes from electron-phonon interaction.

Should I be including then the Bose temperature in the file elph_pw_si itself or in elph_qp_si? It appears to me that there should be something to counterbalance the "smearing" part in DFT analysis.
I am actually following the electron-phonon tutorial in the yambopy documentation.

With regards,
Sitangshu

Re: Smearing problem in qp spectral function!

Posted: Tue Feb 07, 2017 1:44 pm
by sitangshu
Dear Alejandro,

The smearing problem is now solved !!

With regards,

Sitangshu