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 CF$_2$HCl/CF$_3$Br 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 CO$_2$ laser. A method has been described and the first results have been reported. Effective dissociation of CF$_2$HCl molecules (with the yield $\beta\geqslant 10$–$15\%$) in the CF$_2$HCl/CF$_3$Br mixture irradiated by the CO$_2$ laser detuned by more than $15$–$25$ cm$^{-1}$ from the center of the infrared absorption band of CF$_2$HCl molecules vibrationally cooled in the shock wave has been detected at quite low excitation energy densities ($\Phi\leq0.5{-}1.0\,$ J/cm$^2$) at which dissociation of CF$_2$HCl 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.