[Pw_forum] orthogonality of phonon eigenvectors?

Suza W suza.rri at gmail.com
Fri Dec 30 14:41:53 CET 2011


Hello All,

Since eigen displacements are more useful than phonon eigenvectors, it
would be better if QE rather prints eigen-displacements as ABINIT does.

Yours sincerely,
Suza W
Research Associate, RRI, India


On Fri, Dec 30, 2011 at 9:35 AM, Stefano Baroni <baroni at sissa.it> wrote:

> Phonon eigenvectors are solution of a *generalized* eigenvalue equation
> (see the definition in any textbook of classical mechanics, dealing with
> "small oscillations"). As such, they are only orthogonal if all the nuclear
> masses are the same (simple self-evaluation exercise: explain why). HTH - SB
>
> --
> Stefano Baroni, Trieste -- swift message written and sent on the go
>
> On 29/dic/2011, at 10:41, Sonu Kumar <1009ukumar at gmail.com> wrote:
>
> > Dear all QE users,
> >
> > I am not getting the orthogonality of  phonon eigenvectors
> > obtained in xx.dyn  file. However normalization condition is satisfied.
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.quantum-espresso.org/pipermail/users/attachments/20111230/e13bd6b4/attachment.html>


More information about the users mailing list