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.