The ABINIT Users Mailing List ( CLOSED )

[Michel Côté <michel.cote@umontreal.ca>]

Title: Re: [abinit-forum] Re: Symmetry in phonons calculation

Hello Aldo,

Maybe your system is unstable at high pressure? It will help to know exactly what you are working on if it is not a state secret! As always, you should include your input file.

Michel 


Le 26/03/07 09:46, « Matthieu Verstraete » <mjv500@york.ac.uk> a écrit :

> I'm not sure, the rprim look ok, but you have to check with the space 
> group. Angles, etc are also output by abinit, you can check those, and I 
> don't know if the xred are supposed to be highly symmetrical (0.25 or if 
> there value is correct)...
>
> good luck!
>
> Matthieu
>
> On Sun, 25 Mar 2007, Dr. Aldo wrote:
>
> > Dear Matthieu,
> >
> > thanks for your kind reply. I did your suggested changes and the
> > system is still changing the symmetry.. this is quite surprising....
> >
> > Now my input includes
> >
> > acell    3*7.9899636324E+00
> >
> > rprim    5.7005417584E-01  0.0000000000E+00  8.2160710438E-01
> >        -2.8502708792E-01  4.9368140048E-01  8.2160710438E-01
> >        -2.8502708792E-01 -4.9368140048E-01  8.2160710438E-01
> >
> > xred    3*2.4055724610E-01
> >       3*-2.4055724610E-01
> >
> > Is there any other relation that the a(i,j) should follow?..
> >
> > Just to give you an example, I did the zero pressure calculation
> > and the symmetry is fine and the parameters for that case are
> >
> > xred 2.3464570938E-01  2.3464570938E-01  2.3464570938E-01
> >    -2.3464570938E-01 -2.3464570938E-01 -2.3464570938E-01
> > acell 8.3880824458E+00  8.3880824458E+00  8.3880824458E+00
> > rprim 5.5906349543E-01  0.0000000000E+00  8.2912484469E-01
> >      -2.7953174771E-01  4.8416318937E-01  8.2912484469E-01
> >      -2.7953174771E-01 -4.8416318937E-01  8.2912484469E-01
> >
> >
> > Sorry that I am emailing you to yoru account.. I hope it is Ok.
> >
> > Best regards and thanks in advance
> >
> > -aldo.
> >
> >
> >


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  Michel Cote                          tel: +1 (514) 343-5628     
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  Département de physique 
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