This article is cited in
12 papers
OPTICS AND NUCLEAR PHYSICS
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
G. N. Makarov,
A. N. Petin Institute of Spectroscopy, Russian Academy of Sciences, Troitsk, Moscow, 108840 Russia
Abstract:
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
$^2$.
Received: 07.07.2020
Revised: 07.07.2020
Accepted: 08.07.2020
DOI:
10.31857/S1234567820160028
Fulltext:
PDF file (376 kB)