[Pw_forum] dynamical matrix units

[Lorenzo Paulatto]

On 01/15/2014 07:12 PM, Federico Gallino wrote:
> Dear All,
> 
> I refer to a previous topic concerning "units in dynamical matrix files".
> 
> Checking by hands the diagonalization of the dynamical matrix (after dividing by the sqrt
> of masses) by the normalized eigenvectors (provided in the .dyn output) I get a factor of
> 0.0625 (i.e. 2pi*1.D-2) between the diagonalised matrix and the eigenvalues (Ry units)
> provided in .dyn output (e.g. see phonon example 1 for C and Si). Could anyone kindly
> clarify this point?

Dear Federico,
you should tell us exactly what you've done if you want us to find what
you did wrong. Did you take the square root of the eigenvalues?

0.0625 can be many things other than 2pi/100...

best regards



-- 
Dr. Lorenzo Paulatto
IdR @ IMPMC -- CNRS & Université Paris 6
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