Semiclassical Dressed State Theory for the Vibrational Excitation of a Morse Oscillator by Radiation

A uniform semiclassical theory is developed to treat the interaction of a Morse oscillator with a monochromatic radiation field. The correspondence with quantum-mechanical dressed state theory for the Rabi and resonant excitation frequencies is demonstrated, and the semiclassical theory is used to describe resonant one- and two-photon absorption processes. The results are extended to state-to-state vibrational excitation in a polyatomic species.