Theoretical interpretation of rate constants in the chlorination of dichloroethylenes

Abstract

Rate constants are calculated for the addition of Cl to cis- and trans-dichloroethylene (DCE) and for the decomposition of activated trichloroethyl radicals so formed by transition state theory. The calculated bimolecular rate constants are lower by factors of 13 and 4 respectively and the unimolecular rate constant by a factor of 20.

The calculations confirm that internal rotation in both the activated radical and the transition state complex is essentially unhindered but suggest that some of the vibration frequencies in the activated complex are lower than those in the stable trichloroethyl radical.