A Simple Model for Molecular Raman Scattering

Molecular Raman scattering is an inelastic light scattering
process. One shines laser light of a specific frequency on a molecule
and looks for emitted light of a different frequency. The total energy is
conserved by the molecule changing its energy level. We present a very
simple time--dependent model for predicting transition amplitudes for
molecular Raman scattering associated with a short laser pulse when the
frequency of the incident light is close to being resonant with an
electronic transition. Our model leads to remarkably simple expressions
for the transition amplitudes to leading order in both the intensity $\mu$
of the incident laser pulse and the Born--Oppenheimer parameter $\epsilon$
for the molecule.