Spectroscopy in Kinetic Studies of Gas-Phase Reactions.

Abstract

Abstract : New developments in remote sensing, communications, energy systems and other areas of interest depend upon advances in laser technology. Chemical or transfer laser systems hold promise of fulfilling many of these needs. The development of new and better chemical laser systems, however, awaits increased understanding and knowledge of the reactive and spectral characteristics of candidate molecules. The research under this grant has concentrated on obtaining a detailed understanding of metal-oxidant and metal-halogen reactions. Photon yields and product state branching ratios have been determined for many reactions. In many cases it was necessary to develop basic spectroscopic information on the electronically excited product molecules. In the course of these studies, other molecules of atmospheric, combustion, or chemical laser interest also came under scrutiny, and molecular constants were obtained. Various diatomic molecular species have been produced in vacuum flow systems; typically metal vapor entrained in an inert gas is reacted with a halogen or oxidant. These exothermic reactions produce product molecules in excited states whose fluorescence (chemiluminescence) is analyzed. Laser induced fluorescence (photoluminescence) is also used to probe both ground and excited electronic states. The following research summary is organized according to experimental technique. (Author)