F2 LASER (158 NM) PHOTOLYSIS OF CO2 AND HYDROFLUOROCARBON SYSTEMS

F-2 laser (158 nm) photolysis of gas mixtures of CO2 and hydrofluoroca rbons (HFCs) gives the corresponding alcohols and ketones. The initial step of photolysis is a bond breaking reaction to give CO and an elec tronically excited oxygen atom O(D-1). The excited atom is partially i nserted into the HFC C-H bonds and is partially quenched to the triple t atom O(P-3). The dependence of the yields of the alcohols on the gas pressure and the size of the HFC can be explained in terms of the for mation of hot alcohols and collisional relaxation, The insertion rate constant of O(D-1) has been estimated to be (1.5+/-0.3) x 10(-11) cm(3 ) molecule(-1) s(-1) for CF3CF2CH3 based on the quantum yield of CF3CF 2CH2OH production.