Professor Gutman is supported by a grant from the Experimental Physical Chemistry Program to study the kinetics and thermochemistry of elementary reactions involving polyatomic radicals of the second row elements and halogens or hydrogen halides. Experimental techniques include the use of excimer laser photolysis to produce the free radicals under controlled conditions and time-resolved experiments to monitor reactants and products. The radicals to be studied include halo- and perhalomethyls, oxygen containing radicals, nitrogen centered radicals and unsaturated hydrocarbon radicals. Studies of reactions of free radicals of the heavier elements, particularly radicals of silicon, phosphorus, germanium, and arsenic are of particular interest because it is likely that new chemical routes are open to radicals of these elements due to their ability to be in higher valence states than carbon. %%% The objectives of this research are to gain new fundamental knowledge of the kinetics and dynamics of elementary reactions of polyatomic free radicals and to determine important thermochemical properties of these species. The radicals to be studied in this project are important to atmospheric chemistry and combustion; the halogenated radicals are relevant to our search for replacements for the ozone-destroying chlorofluorocarbons. An exciting part of the research is the study of the chemistry of radicals of phosphorus, silicon, arsenic, and germanium which are likely to be involved in chemical vapor deposition (CVD) reactors. Chemical vapor deposition is one of the primary techniques used for growing thin films and coatings used in the semiconductor industry for the fabrication of microelectronic devices.