analysis of phonon DOS/alpha2f with 'mode of vibration'

[topgun]

Dear roxana,

While comparing phonon DOS and Eliasberg spectral function :: how do we know "which part of the curve represent which mode of vibration" ?. If the "mode of vibration" is optical or acoustic or is a component of these two.

Thanks in advance

regards
topgun

[roxana]

Hi,

The acoustic phonons are the three lowest branches with zero frequency at the G-point. If you plot also the phonon dispersion, you can follow the acoustic modes and understand up to which frequency these branches go and get an idea about their contribution to the phonon DOS and Eliashberg spectral function.

Best,
Roxana

[topgun]

Dear roxana maam,

Thank you for the reply.
But, is there any way by which I can know the components of (say) acoustic phonons or optical phonons in the phonon DOS and eliasberg function plots. i.e Longitudinal and transverse acoustic phonons [ LA and TA phonons].

THANKS IN ADVANCE

regards
topgun