rate constants for Cl + O 3 1 Rate constants for the reaction of Cl atoms with O 3 at temperatures from 298 to 184 K

Using the standard, low pressure, discharge-flow technique, with resonance fluorescence in the vacuum ultraviolet to observe Cl atoms, rate constants have been determined for the reaction of Cl atoms with O3 at temperatures down to 184 K. The measured rate constants for 298184 K fit the Arrhenius expression: k(T) = (3.6 ± 0.7) × 10 exp(( 310 ± 50 K) / T) cm molecule s. The results extend the data on this key atmospheric reaction to slightly lower temperatures. The data are in fairly good agreement with those currently in the literature but suggest that the rate constant approximately 15% lower than that given by currently recommended rate expressions at the lowest temperatures found in the stratosphere. * Correspondence to: I. W. M. Smith ([email protected]) IJCK paper: rate constants for Cl + O3