I am curious whether or not there is a connection between the group theoretical assignment of phonon modes and LO-TO splitting. For example, is it true that the frequency of a gerade mode will depend on the direction of approach to $\Gamma$ in reciprocal space? Conversely, is the frequency of an ungerade mode independent of the direction of approach?
Forgive my lack of group theory understanding if this is a silly question.
Thank you,
CW279