The kinetics of the gas-phase reactions of chlorine atoms with dichloromethane (CH2Cl2) and D-dichloromethane (CD2Cl2) was studied using the relative rate method with Cl + CH3Br as the reference reaction. The rate constants for H-abstraction from CH2Cl2 (k(H)) and D-abstraction from CD2Cl2 (k(D)) were measured in the temperature range of 298-527 K and at a total pressure of 100 Torr using N-2 as a diluent. The temperature dependencies of the rate constants (with the 2 sigma error limits) are described by the expressions: k(H) = (8.69 +/-0.82) x 10 (12) x exp(-955 +/- 20/T) and k(D) = (6.98 +/- 0.91) x 10 (12) x exp(-1285 +/- 25/T) cm(3) molecule (1) s (1). The kinetic isotope effect, described by the ratio k(H)/k(D), was found of 3.8 +/-0.2 at room temperature. (C) 2011 Elsevier B. V. All rights reserved.