[Pw_forum] A question about force constants calculation output

[Paolo Giannozzi]

On Dec 30, 2009, at 19:16 , Zhen Huang wrote:

> ph.x calculation generated files alas.dynX where X goes from 0 to 8.
> In the file alas.dyn0 it gives the k points. Seems in the other  
> dynX files
> for example .dyn1 it gives force constants of q=(0.0, 0.0, 0.0)   
> and .dyn2
> gives force constants of q=(-0.25   0.25  -0.25), (0.25  0.25   0.25),
> ( 0.25  -0.25  -0.25), and such.

correct

> On the other hand, matdyn.x also give force constants file  
> alas444.fc which is also partialy attached. What is the T matrix   
> and Matrix 1 and 2 labeled below.

do you really need to know the contents of internal files?

The "T" matrix, as you call it, is the dielectric tensor, while  
matrix "1"
and "2" should be the effective charge tensors for atom 1 and 2.
For the rest, a quick search in the mailing list archives yields this:
    http://www.democritos.it/pipermail/pw_forum/2005-April/002408.html

P.
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Paolo Giannozzi, Dept of Physics, University of Udine
via delle Scienze 208, 33100 Udine, Italy
Phone +39-0432-558216, fax +39-0432-558222