[Pw_forum] how to obtained the eigndisplacement by eignvector in PWSCF

[Stefano Baroni]

I do not quite get the question.
It is the mass of Pb as found in any perdiodic table: 207.2 amu (see  
www.webelements.com)

Atomic masses should also be specified in the "ATOMIC_SPECIES" card  
whose format, in the present case, should be something like:

Pb 207.2 Pb_pseudopotential_file_name

Are you confused instead by the negative value of the frequency?  
(this has nothing to do with masses)

Hope this helps - Stefano

On Jun 5, 2006, at 4:23 PM, 针叶 朱 wrote:

> Dear all user:
> i have calculated the phonon of PbTiO3, and i have obtained  
> eignvector of atom under each mode.
> for example:
>   omega( 1) =      -4.221301 [THz] =    -140.808368 [cm-1]
>  ( -0.092855  0.000000 -0.004178  0.000000  0.001020  0.000000 )
>  ( -0.185613  0.000000 -0.008352  0.000000  0.002040  0.000000 )
>  (  0.598322  0.000000  0.026924  0.000000 -0.005371  0.000000 )
>  (  0.598322  0.000000  0.021990  0.000000 -0.006576  0.000000 )
>  (  0.488678  0.000000  0.026924  0.000000 -0.006576  0.000000 )
>     now i have kown the eigndisplacement  |u> = M^(-1/2) | v>.
> but i am confused with mass M. for example, for Pb atom in PbTiO3.  
> how much is mass of Pb in equation above?
> please grive me some construction!
>
> Regards
>
>                                            zhuzhenye
>
> 抢注雅虎免费邮箱-3.5G容量，20M附件！

---
Stefano Baroni - SISSA  &  DEMOCRITOS National Simulation Center -  
Trieste
[+39] 040 3787 406 (tel) -528 (fax) / stefanobaroni (skype)

Please, if possible, don't  send me MS Word or PowerPoint attachments
Why? See:  http://www.gnu.org/philosophy/no-word-attachments.html



-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.quantum-espresso.org/pipermail/users/attachments/20060606/6fb8730b/attachment.html>