Primary steps in the photolysis of cis-1,2-dichloroethylene

The photolysis of cis-1,2-dichloroethylene has been investigated in the presence of I₂ as a function of incident wavelength and as a function of initial cis pressure. The results indicate that at ± > 2200Å the following primary processes occur: The lifetime of the excited state yielding the above products is estimated at about 2.4×10^?9 sec. At shorter wavelengths additional C₂H₂ is produced by decomposition of a vibrationally excited C₂H₂Cl radical. Scavenging of the CHClCH radical by I₂ produced trans and cis-CHClCHl in a ratio of 4 to 1, respectively.