[Pw_forum] phonon dos normalization

[Paolo Giannozzi]

On Friday 09 September 2005 11:10, W. YU wrote:

> After several testing, I found that the phonon density of
> states from the PWscf calculations are normalized to six 
> times the number of atoms in a unit cell

there is no deep reason. The phonon DOS is calculated by the
same routine that calculates the electron DOS. This is normalised 
to the number of electrons, i.e., in the spin-unpolarised case, to
two times the number of states. In the phonon case, this means 
2 * (3 * # atoms). 

You can easily change this to whatever you like. In the next
version the normalisation of the phonon dos will be explicitly 
written. Thank you for bringing this to our attention

Paolo

-- 
Paolo Giannozzi             e-mail:  giannozz at nest.sns.it
Scuola Normale Superiore    Phone:   +39/050-509876, Fax:-563513 
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