Collisionless CO2 laser-induced photodissociation of sulfur hexafluoride in a molecular beam experiment

Many polyatomic molecules exhibit an anomalous absorption behavior when exposed to high-power infrared laser radiation. This has been studied in a molecular beam experiment, where vibrational superexcitation and dissociation of SF6 molecules under collisionless conditions was induced by a CO2 laser over a wide range of laser flux densities. By mass spectrometric detection it was possible to identify vibrational excitation in molecules which were not dissociated. The results provide unambiguous insight into the laser energy dependence of the primary dissociation and show the highly isotopically selective nature of these processes