New results for laser isotope separation using low-energy methods

Today, research aimed at the development of low-energy methods of molecular laser isotope separation (MLIS) is relevant and in demand. The main goal of these studies is to find efficient and cost-effective methods that can be used as the basis for the technology of laser separation of uranium isotopes, as well as other elements. To date, a number of approaches to the implementation of low-energy methods of MLIS using infrared (IR) lasers have been proposed. Many of these approaches are not well understood and/or are difficult to put into practice. Some of them are considered to be promising and require further study. These include the method of isotope-selective suppression of the clustering of molecules using IR lasers during gas-dynamic expansion at a nozzle exit and the method of isotope-selective IR dissociation of small molecular van der Waals clusters. A review of recent results obtained using these two methods is presented. The experimental facilities and research methods are briefly described, and the choice of the objects of study is substantiated. Results obtained with model $\rm{SF}_6$ and $\rm{CF}_3\rm{Br}$ molecules are analyzed with reference to studying the process of isotope-selective suppression of the clustering of molecules among themselves and with atoms of an argon carrier gas, as well as the process of isotope-selective IR dissociation of small homogeneous and mixed clusters of $({\rm SF_6})_m{\rm Ar}_n$ and $({\rm CF_3Br})_m{\rm Ar}_n$ (where $m = 1-2$ and $0 \le n \le 5$ are the numbers of molecules and atoms in the clusters, respectively). The results presented suggest that these methods can be used for the separation of isotopes in molecules containing isotopes of heavy elements, which have a slight isotopic shift in the IR absorption spectra.