Re: [Phonopy-users] eigenvector and displacement of phonon

[Atsushi T. <atz...@gm...>]

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 <lor...@gm...> 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
> Pho...@li...
> https://lists.sourceforge.net/lists/listinfo/phonopy-users
>
>


-- 
Atsushi Togo
http://atztogo.github.com/
atz...@gm...