Phonon pdos

ASE
1

Dear developers and users,

I am following the documentation of DOS for phonons and there is an indices in get_dos method that you can provide a list. Adding this list did not change the DOS. After looking at the code, this function is not implemented.

Also, I checked the whole documentation afterwards, and I found some modules in ase.vibrartions. Is it possible to use the vibration module with phonon? I only need the pdos capability. If anyone knows how to obtain that, it would be appreciated.

Thanks for ASE, it helps a lot.
Best,

2

Hi Daniel,

essentially the differences between “vibrations” and “phonons” for ASE purposes are:

  • phonons are represented by the Hessian of a supercell (“force constants”), which allows Fourier interpolation to different q-points
  • vibrations can also be used with periodic systems but there is no supercell concept
  • refactoring/improvements to vibrations are further progressed :sweat_smile:

So if your system can be represented well without a supercell, it would be ok to use the vibrations module instead. If you need the Fourier interpolation to sample q-space, then it’s a phonon problem.

You are right that the indices argument to Phonons.dos() and Phonons.get_dos() seems to be broken. Would you be able to open an Issue about that on the Issue tracker? Issues · ase / ase · GitLab . If it is not easy to fix then it should probably be removed…

3

Thanks Adam,

I could not reach you before. From what I could read from the code, maybe it is easier to remove the feature.
Best,