[Pw_forum] LO-TO splitting in molecules

[xirainbow]

> I am not sure weather LO-TO splitting could be observed in molecules.
         I do not think so. LO-TO splitting originates from the long
range coulomb interaction and ordered dipole vibration. The latter
does not exist in molecular.

> My  Further qusetion regarding the RAMAN modes.  Whether pure Raman modes (i.e.
> Infrared inactive modes and only Raman acive)  will give any LO-TO splitting.
         No.