Gas‐phase reactivity study of O( 3 P) atoms with trans ‐CHClCHCl and CHClCCl 2 at 298 K: Comparison to reactions with some other substituted ethenes

Absolute rate coefficients for the gas‐phase reactions of trans ‐dichloroethene and trichloroethene with O( 3 P) atoms have been measured at 298 K using a discharge flow tube coupled to a chemiluminescence detection system. The observed rate constant values are (2.2 ± 0.4) × 10 −13 and (1.4 ± 0.2) × 10 −13 cm 3 molecule −1 s −1 , respectively. The experiments were carried out under pseudo‐first‐order conditions with [O( 3 P)] o ≪ [alkene] o . These results are compared to those of O atom reactions with other chloroethenes and with different electrophiles, such as OH and NO 3 . Different factors that affect the rate of addition to the double bond are considered. The rate constants for these reactions do not correlate in a simple manner with the experimental ionization potential, as is the case in the alkene and methyl‐substituted alkene reactions. © 2001 John Wiley & Sons, Inc. Int J Chem Kinet 33: 415–421, 2001