Characteristics of the absorption of high-intensity infrared radiation by molecules (review)

A review is given of the mechanisms of excitation of the vibrational levels of polyatomic molecules over a broad range of laser pulse durations. The part played by the rotational structure of the levels in compensating for the anhannonicity of the molecular vibrations is indicated. The theoretical conclusions are compared with the existing experimental results for SF₆ and BCl₃, molecules. The future trends of research on multiphoton excitation of molecules by high-intensity infrared radiation are outlined.