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["matthieu verstraete" <matthieu.jean.verstraete@gmail.com>]

You have to do this by hand for the moment. The idea is that for each mode you calculate the contribution in the phonon eigenvectors (normalized) which is due to a given atom, e.g.

weight(lambda, q, tau) = sum_i  |u_lambda,q (i, tau)|^2

for direction i, atom tau, phonon mode lambda and qpoint q. The sum of these over all tau gives 1 (for a given lambda,q), so you have a weight. Multiply this by the phonon dos, and you get a PDOS. This also works fine for crystals and any other system.

PDOS_tau (omega) = sum_q,lambda  weight(lambda, q, tau) delta(omega-omega_q,lambda)

It should be fairly easy to add this to the anaddb output at some point - someone may even have already done it! I notice Matteo Giantomassi has a routine mkphdos with similar functionality: Matteo does this work yet?

Matthieu

On Mon, Dec 1, 2008 at 9:02 AM, Zhenhua Zeng <myid520@163.com> wrote:

Dear Prof. Xavier Gonze and Dr. Matthieu Verstraete,

I have the similar but different question.
My question is that can phonon DOS be projected to the particular atoms? just like projected electron DOS.

It seem meanningless for bulk calculation. But for slab calculation, It can show some surface phonon model by projecting to atoms.
For example, Felix Yndurain and  Manuel Perez Jigato found Localized Surface Phonons using Frozen-phonon method through analyzing dynamical matrix.
'First Principles Calculation of Localized Surface Phonons and Electron-Phonon Interaction at Pb(111) Thin Films' PRL 100,205501 (2008) see the link below.
http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=PRLTAO000100000020205501000001&idtype=cvips&gifs=yes

If The phonon dos can be projected to particular atoms, then it will be easier to identify this localized surface phonon model.

Best Wishes
Zhenhua Zeng

-------------------------------------------------------------
From：Xavier Gonze
sent:：2008-11-30 19:49:37
To：forum@abinit.org
Subject：Re: [abinit-forum] projected Phonon DOS

>
>Dear Patrick Hillyard,
>
>On 02 Apr 2007, at 19:06, Patrick B. Hillyard wrote:
>
>> Dear Abinit users,
>>
>> I am interested in calculating a projected phonon Density of
>> States.  In the Reponse Function, the capability exists to
>> calculate both the total phonon DOS and also phonon dispersion
>> curves.  I am interested in taking the phonon DOS (integrated over
>> a fine mesh in the BZ) and projecting the displacement vectors onto
>> a given reciprocal lattice vector.  Is this possible?
>
>Well, this is indeed possible, but I am afraid that you will have to
>hack some subroutine
>of the ANADDB code, likely thm9.F90 , where the phonon DOS is
>computed ...
>
>Good luck,
>Xavier
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-- 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Dr. Matthieu Verstraete

European Theoretical Spectroscopy Facility (ETSF) 
Dpto. Fisica de Materiales, 
U. del Pais Vasco,            
Centro Joxe Mari Korta, Av. de Tolosa, 72,   Phone: +34-943018393
E-20018 Donostia-San Sebastian, Spain        Fax  : +34-943018390

Mail : matthieu.jean.verstraete@gmail.com
http://www-users.york.ac.uk/~mjv500