The 193 nm photodissociation of CH2=CClF

Abstract

The photodissociation of CH2=CClF at 193 nm has been studied by product translational spectroscopy. A total of five primary dissociation channels was detected for the products of Cl (fast), HCl, HF, Cl (slow), and F in the decreasing order of relative yield. Product translational energy distributions have been measured for these reaction products. While a thermal-like distribution was detected for the slow Cl and F atoms, a nonthermal distribution was determined for the fast Cl atom and the molecular elimination of HCl and HF. Apart from the fast Cl atom with anisotropy parameter β=0.5, the remaining products recoil isotropically following photolysis with linearly polarized light. By analogy with the photodissociation of chloroethylenes, these products are found to originate from two potential energy surfaces. In addition to the primary dissociation channels, we have detected the secondary products of F+C2H2 from the internally excited α-fluorovinyl radical through a fast fragment isomerization.