Sudden jumps in GW band structure

Concerns issues with computing quasiparticle corrections to the DFT eigenvalues - i.e., the self-energy within the GW approximation (-g n), or considering the Hartree-Fock exchange only (-x)

Moderators: Davide Sangalli, andrea.ferretti, myrta gruning, andrea marini, Daniele Varsano

Post Reply
riemann
Posts: 5
Joined: Sun Oct 04, 2015 9:54 am

Sudden jumps in GW band structure

Post by riemann » Sun May 23, 2021 7:38 am

Dear All,

I'm doing GW correction to the band structure which is obtained from DFT calculations via Quantum Espresso. As is attached, as you can see, instead of smoothly varying band structure I got a non-smooth band structure (purple line+point). Could you please guide me on how to fix it and where does this error arises?

Thank you in advance.

Regards,
Vahid
You do not have the required permissions to view the files attached to this post.

User avatar
claudio
Posts: 448
Joined: Tue Mar 31, 2009 11:33 pm
Contact:

Re: Sudden jumps in GW band structure

Post by claudio » Sun May 23, 2021 8:42 am

Dear Vahid

which version of Yambo are you using?

best
Claudio
Claudio Attaccalite
[CNRS/ Aix-Marseille Université/ CINaM laborarory / TSN department
Campus de Luminy – Case 913
13288 MARSEILLE Cedex 09
web site: http://www.attaccalite.com

riemann
Posts: 5
Joined: Sun Oct 04, 2015 9:54 am

Re: Sudden jumps in GW band structure

Post by riemann » Sun May 23, 2021 9:46 am

Dear Claudio,

I'm using Yambo version 5.0.

Regards,
Vahid

--Dr. Vahid Derakhshan Maman
Postdoctoral Research AssociateUtrecht University, Debye Institute for Nanomaterials Science
Heidelberglaan 83584 CS Utrecht

User avatar
Daniele Varsano
Posts: 3773
Joined: Tue Mar 17, 2009 2:23 pm
Contact:

Re: Sudden jumps in GW band structure

Post by Daniele Varsano » Mon May 24, 2021 8:00 am

Dear Vahid,
can you post your input/report file for the GW calculation and ypp runs?
Besides the jumps, it seems that most of the energies are not corrected by the GW calculation.

Best,
Daniele
Dr. Daniele Varsano
S3-CNR Institute of Nanoscience and MaX Center, Italy
MaX - Materials design at the Exascale
http://www.nano.cnr.it
http://www.max-centre.eu/

riemann
Posts: 5
Joined: Sun Oct 04, 2015 9:54 am

Re: Sudden jumps in GW band structure

Post by riemann » Mon May 24, 2021 8:53 am

Dear Daniele,

Please find the input/output files attached.

Regards,
Vahid

--Dr. Vahid Derakhshan Maman
Postdoctoral Research Associate Utrecht University, Debye Institute for Nanomaterials Science
Heidelberglaan 83584 CS Utrecht
You do not have the required permissions to view the files attached to this post.

User avatar
Daniele Varsano
Posts: 3773
Joined: Tue Mar 17, 2009 2:23 pm
Contact:

Re: Sudden jumps in GW band structure

Post by Daniele Varsano » Tue May 25, 2021 8:41 am

Dear Vahid,

please note you are not including qp corrections in your band interpolation.
In order to include them you need to add in your ypp input file the keyword:

Code: Select all

GfnQPdb= "E < ./BND1/ndb.QP"
Next, the algorithm you are using for band interpolation seems it is not giving accurate results, you can try to modify the input file using:

Code: Select all

INTERP_mode= "BOLTZ" 


Best,
Daniele
Dr. Daniele Varsano
S3-CNR Institute of Nanoscience and MaX Center, Italy
MaX - Materials design at the Exascale
http://www.nano.cnr.it
http://www.max-centre.eu/

Post Reply