[Pw_forum] symmetry of phonon modes

[Dal Corso Andrea]

Please check the troubleshooting section of the user guide at the point:

pw.x doesn’t find all the symmetries you expected

Hope this helps.

Andrea


On Wed, 2008-03-26 at 13:51 +0530, Munima Bora Sahariah wrote:
> 
> Dear PWscf users,
> 
> I am doing some phonon calculations in a wurtzite material having space
> group P6_3 mc (186). Typically, for this structure, we should get 12
> phonon branches grouped into the 2E_2 + 2E_1 + 2A_1 + 2B_1 irreducible
> representation at gamma point. However in my phonon output file, I get 8
> phonon modes which are marked  as A' and rest 4 as A'' which fall into
> some other point groups. I am using espresso-3.2.3.
> 
> Could anyone please explain what is going wrong?  Moreover I would like to
> know how one can determine the symmetry labels of a given phonon mode from
> the pwscf outputs without using the standard symmetry analizer included in
> espresso-3.2 onwards.
> 
> I am new to this pwscf code and to phonon  calculations as well. So I
> would highly appreciate some elaborate suggestion/explanation in this
> matter.
> 
> Thanks
> 
> 
> 
> 
> _____________________________
> Dr. Munima B. Sahariah
> PI, DST Fast Track Project
> IASST, Guwahati
> Assam, INDIA
> 
> 
> -----------------------------------------------------------------------------------
> This email was sent from IIT Guwahati Webmail. If you are not  the intended recipient, please contact the sender by email and delete all copies; your cooperation in this regard is appreciated.
> http://www.iitg.ac.in
> _______________________________________________
> Pw_forum mailing list
> Pw_forum at pwscf.org
> http://www.democritos.it/mailman/listinfo/pw_forum
-- 
Andrea Dal Corso                    Tel. 0039-040-3787428
SISSA, Via Beirut 2/4               Fax. 0039-040-3787528
34014 Trieste (Italy)               e-mail: dalcorso at sissa.it