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.