Intense Infrared Laser-Induced Radiation–Collision Involvement of Molecules That Do Not Absorb Laser Radiation in Resonance with a Laser Field in a Two-Component Molecular Medium

Effective radiation–collision involvement of molecules that do not absorb laser radiation in resonance with a laser field in a two-component molecular medium that includes molecules absorbing laser radiation and is subjected to intense infrared laser radiation has been detected. Experiments have been performed with the CF2HCl/CF3Br mixture (at the 1/1 pressure ratio), where molecules are under nonequilibrium thermodynamic conditions in a shock wave, which has been formed in front of the solid surface on which a gas-dynamically cooled intense pulsed molecular beam is incident. Molecules have been excited by the pulsed radiation of a СО2 laser. A method has been described and the first results have been reported. Effective dissociation of CF2HCl molecules (with the yield β ≥ 10–15%) in the CF2HCl/CF3Br mixture irradiated by the CO2 laser detuned by more than 15–25 cm–1 from the center of the infrared absorption band of CF2HCl molecules vibrationally cooled in the shock wave has been detected at quite low excitation energy densities (Φ ≤ 0.5–1.0 J/cm2) at which dissociation of CF2HCl molecules in a pure gas hardly occurs. The results can be applied to separate isotopes using the method of isotope-selective infrared laser dissociation of molecules.