PHOTOFRAGMENTATION OF OCLO CLUSTERS IN A SUPERSONIC JET AT 360 AND 275 NM

Using photofragment translational energy spectroscopy, we studied the photochemical decay of chlorine dioxide (OClO) clusters ina cold beam with Ne as carrier gas. The products ClO, OClO, Cl2O3, and Cl2O4 gener ated by 360 nm excitation were-except for the fast ClO fragments which arise from monomer photodissociation-found to be slow moving and with broad time-of-flight distributions. They show an approximately therma l translational energy distribution of 300-500 K and a recoil anisotro py beta approximate to 0, as measured for the representative OClO prod uct. Furthermore with excitation at 275 nm where the OClO monomer has no absorption, the same slow moving product species were created, indi cating that they are evaporation products of excited cluster species, A reaction scheme is proposed which includes. unimolecular photochemic al decays and bimolecular cage reactions of initially formed fragments among themselves and with cluster constituents.