Hello All, <br><br>Since eigen displacements are more useful than phonon eigenvectors, it would be better if QE rather prints eigen-displacements as ABINIT does. <br><br>Yours sincerely, <br>Suza W<br>Research Associate, RRI, India<br>
<br><br><div class="gmail_quote">On Fri, Dec 30, 2011 at 9:35 AM, Stefano Baroni <span dir="ltr"><<a href="mailto:baroni@sissa.it">baroni@sissa.it</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
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<br>
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Stefano Baroni, Trieste -- swift message written and sent on the go<br>
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On 29/dic/2011, at 10:41, Sonu Kumar <<a href="mailto:1009ukumar@gmail.com">1009ukumar@gmail.com</a>> wrote:<br>
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> Dear all QE users,<br>
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> I am not getting the orthogonality of phonon eigenvectors<br>
> obtained in xx.dyn file. However normalization condition is satisfied.<br>
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