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calculation of phonon spectrum
Posted: Mon Mar 14, 2011 11:15 am
by Amal Giri
Dear All,
Is it possible to calculate phonon spectrum of metals in which point defects
and dislocation have been introduced by means of irradiation or deformation? If it is possible then how it can be done?
Thanks
Re: calculation of phonon spectrum
Posted: Mon Mar 14, 2011 3:32 pm
by Boris
Hi
Basically, I would say that abinit can calculate the phonon spectrum of any materials, provided you don't use the PAW approach. So for the moment you're limited to pseudopotentials.
If you want to calculate the phonon spectrum in a defective system, you just have to use a supercell. Then you use density functional perturbation theory to calculate the phonon frequencies (see tutorials 1 and 2 of the response function). But I guess this will be a computational demanding calculation, since in defective supercells, you have very few symmetries, and a lot of atoms will have to be displaced.
Boris
Re: calculation of phonon spectrum
Posted: Tue Mar 15, 2011 6:07 am
by Amal Giri
Thank you Mr. Boris. I am trying according to your suggestion.
But I have another quarry. Can I calculate thermal conductivity of that defective material with the help of abinit ?
Re: calculation of phonon spectrum
Posted: Tue Mar 15, 2011 3:20 pm
by Boris
Hi
In principle, you can. It is explained in the tutorials. But as I said, you will have to use a (more or less) large defective supercell, so it might be difficult. But it should be tried.
Boris