AbstractThe following reactions: equation image were studied over the temperature ranges 533–687 K, 563–663 K, and 503–613 K for the forward reactions respectively and over 683–763 K, for the back reaction. Arrhenius parameters for chlorine atom transfer were determined relative to the combination of the attacking radicals. The ΔHr°(1) = −3.95 ± 0.45 kcal mol−1 was calculated and from this value the ΔH∮(C2F5Cl) = −2.66.3 ± 2.5 kcal mol−1 and D(C2F5‐Cl) = 82.0 ± 1.2 kcal mol−1 were obtained. Besides, the ΔHr°(2) was estimated leading to D(CF2ClCF2Cl) = 79.2 ± 5 Kcal mol−1. The bond dissociation energies and the heat of formation are compared with those of the literature. The effect of the halogen substitutents as well as the importance of the polar effects for halogen transfer processes are discussed.