Yambo Community Forum

Dear all,

I'm trying to get DOS plot of crystalline Si using ypp based on the output of COHSEX calculations. My problem is that the plot obtained from ypp shows much lower density compare to that from pwscf. The other problem is that ypp DOS plot shows larger energy range (almost 5ev) in both valance and conduction bands. I just wanted to know if these problems are normal or not? If it's normal what is the physics behind them. If it's not normal, How can I fix them?

Any comments would be highly appreciated.

I attached my input files and dos plots.

Best,
Reza

Dear Reza,

My problem is that the plot obtained from ypp shows much lower density compare to that from pwscf.

Mosto probably there is a different renormalization factor, we can have a look at it.

The other problem is that ypp DOS plot shows larger energy range (almost 5ev) in both valance and conduction bands.

Well, this is not a real problem, you can define the range in an arbitrary way. Of course it depend on the number of bands you include. Anyway please
note that yambo at difference of pwscf set the Fermi level (or valence band maximum) at zero energy. If you align the VBM the energy range turns to be very similar.

Best,
Daniele

Dear Daniele
I have the same problem " plot obtained from ypp shows much lower density compare to that from pwscf". however, I did not notice your reply. This may be because I select limited bands in GW calculations?
tell me please, how can I fix this issue?
Best
Aref

Dear Aref,

this is just a matter of normalisation and it is harmless.
Note that, at difference of QE, Yambo set the zero to the VBM, if you want to compare them you need to shift the origin.
I would also use a larger smearing both in Yambo and QE.

Best,
Daniele