This research, part of the Experimental Physical Chemistry Program, seeks to understand the basic dynamics of simple gas phase chemical reactions. It uses techniques of laser spectroscopy to probe the energetics of product and transient species. The reaction chosen for study is K + NaCl Na* + KCl. Techniques of laser induced fluorescence fluorescence will be used to probe the energetics of the Na* at different energies using cooled beams. For the K + NaCl system (and similar systems) attempts will be made to observe the transition species, KNaCl, formed in the supersonic beam using the methods of laser induced fluorescence. In particular the vibrational and energy levels of these complexes will be observed and mapped in order to provide a generic understanding of the energetics and dynamics of these Transition Region Species (TRS).