Abstraction vs exchange in the reaction of D+HCl

Abstract
The gas phase reaction of D with HCl was studied at room temperature by the method of flash photolysis, with resonance fluorescence detection of S, H, and Cl atoms. The D and Cl atoms were observed to decay exponentially, whereas no H atom signal from the exchange reaction was detectable. From the calibrated sen;sitiavity of the H atom detector, an upper limit of 0.002 was set for the ratio of rate constants for the exchange vs abstraction channels.