phonopy-users

 [Phonopy-users] eigenvector and displacement of phonon From: 김수란 - 2013-05-14 07:39:21 Attachments: Message as HTML Hello During the study of formulations page in phnonopy homepage, I found a strange thing. http://phonopy.sourceforge.net/theory.html#dynamical-matrix In this section, until third equation, [image: \sum_{j \alpha j' \beta}e_\alpha(j',\mathbf{q}\nu)^* D_{\alpha\beta}(jj',\mathbf{q}) e_\beta(j',\mathbf{q}\nu') = [\omega(\mathbf{q}\nu)]^2 \delta_{\nu\nu'}.] eigenvector *e *follows Sigma(e*e)"m_j"=delta However the output eigenvector in phononpy follows Sigma(e*e)=delta. (Which is written in phonopy-workshop.pdf in homepage) And this output eigenvector is used for calculating displacement using forth equation. Therefore eigenvectors in third equation and forth equation look different i.e. eigenvector in third equation follows Sigma(e*e)"m_j"=delta eigenvector in forth equation follows Sigma(e*e)=delta Which one is the really calculated in phonopy?? eigenvector in third equation or eigenvector in forth? p.s. minor bug report in moulation.yaml. I used phonopy 1.6.2 version. When I calculated the multi modulation, e.g. MODULATION = 1 1 1, 1/2 0 1/2 1 1, 1/2 1/2 1/2 1 1 The q-position above the eigenvector not displacement always is written last q position (in this case 1/2 1/2 12) So I think there should be q = mode[0] at line 248 in modulation.py. Best regards Sooran Kim 
 Re: [Phonopy-users] eigenvector and displacement of phonon From: Atsushi Togo - 2013-05-15 01:55:26 Attachments: Message as HTML Hi, I confirmed your bug report. I will fix it. For eigenvectors, the second equation is wrong. I will fix it. Thank you. Togo On Tue, May 14, 2013 at 4:39 PM, 김수란 wrote: > Hello > > During the study of formulations page in phnonopy homepage, > I found a strange thing. > > http://phonopy.sourceforge.net/theory.html#dynamical-matrix > > In this section, until third equation, > [image: \sum_{j \alpha j' \beta}e_\alpha(j',\mathbf{q}\nu)^* > D_{\alpha\beta}(jj',\mathbf{q}) e_\beta(j',\mathbf{q}\nu') = > [\omega(\mathbf{q}\nu)]^2 \delta_{\nu\nu'}.] > > eigenvector *e *follows Sigma(e*e)"m_j"=delta > > However the output eigenvector in phononpy follows Sigma(e*e)=delta. > (Which is written in phonopy-workshop.pdf in homepage) > And this output eigenvector is used for calculating displacement using > forth equation. > > Therefore eigenvectors in third equation and forth equation look different > i.e. eigenvector in third equation follows Sigma(e*e)"m_j"=delta > eigenvector in forth equation follows Sigma(e*e)=delta > > Which one is the really calculated in phonopy?? > eigenvector in third equation or eigenvector in forth? > > p.s. minor bug report in moulation.yaml. > I used phonopy 1.6.2 version. When I calculated the multi modulation, > e.g. MODULATION = 1 1 1, 1/2 0 1/2 1 1, 1/2 1/2 1/2 1 1 > The q-position above the eigenvector not displacement > always is written last q position (in this case 1/2 1/2 12) > > So I think there should be q = mode[0] at line 248 in modulation.py. > > Best regards > Sooran Kim > > > > > > > > ------------------------------------------------------------------------------ > AlienVault Unified Security Management (USM) platform delivers complete > security visibility with the essential security capabilities. Easily and > efficiently configure, manage, and operate all of your security controls > from a single console and one unified framework. Download a free trial. > http://p.sf.net/sfu/alienvault_d2d > _______________________________________________ > Phonopy-users mailing list > Phonopy-users@... > https://lists.sourceforge.net/lists/listinfo/phonopy-users > > -- Atsushi Togo http://atztogo.github.com/ atz.togo@...