PW users: please read. Optical strengths warning!

Come here to discuss issues with using the p2y converter from PWscf to Yambo, how to best run PWscf , link with the IOTK library, and so on.

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andrea marini
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PW users: please read. Optical strengths warning!

Post by andrea marini » Fri Mar 20, 2009 11:02 am

When calculating optical properties a potentially relevant contribution comes from the non-local components of the pseudopotential. For a definition of this contribution please check, for example, section V (Eqs. 7,8 and 9) of this article .

In yambo this contribution is contained in the core databaes (n)s.kb_pp.
This database is extracted by default when using Abinit by the a2y interface.

The importance of this contribution depends on the specific system and on the strength of non-locality in the pseudopotentials. This article (Fig. 4 and 5) shows that there is a dramatic change in the optical absorption of d-metals due to the inclusion of this term. For s and p electrons this contribution depends on the specific systems (see here
for more details).

Unfortunately we have not yet coded this contribution in the p(w)2y(ambo) interface.

As a consequence PW users are strongly invited to perform a test calculation by using abinit to estimate the importance of this contribution for their specific system.
Andrea MARINI
Istituto di Struttura della Materia, CNR, (Italy)

nkxirainbow
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Joined: Wed Jul 22, 2009 6:12 am

Re: PW users: please read. Optical strengths warning!

Post by nkxirainbow » Thu Jul 23, 2009 4:37 am

I can not open "article" :oops:
Hui Wang
Nankai Universty, China
nkxirainbow@gmail.com

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andrea marini
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Re: PW users: please read. Optical strengths warning!

Post by andrea marini » Thu Jul 23, 2009 8:24 am

nkxirainbow wrote:I can not open "article" :oops:
Sorry :? I fixed the link. Now it works.

Thanks !
Andrea MARINI
Istituto di Struttura della Materia, CNR, (Italy)

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Daniele Varsano
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Re: PW users: please read. Optical strengths warning!

Post by Daniele Varsano » Wed Apr 29, 2020 8:00 am

This is an old warning. The non-local components of the pseudopotential in the optical strengths starting from a QE calculation has been coded in Yambo years ago. By default it is included. As it can be computational quite demanding you can deactivate it by renaming the ns.kb_pp_pwscf in your SAVE directory.
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/

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