Strong increase in the efficiency of isotope-selective infrared laser dissociation of molecules under nonequilibrium thermodynamic conditions in a shock wave by means of the use of a mixture with a resonantly absorbing gas

A strong increase in the efficiency of isotope-selective infrared laser dissociation of molecules (by an example of CF$_2$HCl) under nonequilibrium thermodynamic conditions in a shock wave has been reached by using a mixture with a resonantly absorbed gas (CF$_3$Br). It has been shown that the dissociation yield of CF$_2$HCl molecules irradiated in a mixture with CF$_3$Br molecules is more than a factor of $5$–$10$ higher than the dissociation yield in the case of their irradiation in the form of pure gas. The dissociation threshold of CF$_2$HCl molecules in the mixture with CF$_3$Br molecules also decreases significantly from $\approx\,1.5$–$2.0$ to $0.2$–$0.3$ J/cm$^2$). This allows the efficient isotope-selective infrared dissociation of molecules at low exciting energy densities ($\Phi\leq1.0{-}1.5\,$ J/cm$^2$), as well and increasing the selectivity of the process. The method has been described and the first results have been presented. The dissociation of CF$_2$HCl molecules selective in the $^{35}$Cl and $^{37}$Cl isotopes with the enrichment factor $K_{\text{enr}}(^{35}\text{Cl}/^{37}\text{Cl})=0.90\pm0.05$ is implemented when a CF$_2$HCl/CF$_3\text{Br}=1/1$ mixture is irradiated by the $9\mathrm{R}(30)$ ($1084.635$ cm$^{-1}$) line of a CO$_2$-laser at an energy density of $\Phi\approx1.3\,$ J/cm$^2$.