Reactions of protonated water clusters with chlorine nitrate revisited

Potential reaction mechanisms of D+(D2O)(n) (n = 4-30) with chlorine nitrate (ClONO2) have been investigated using a fast flow reactor operated under thermal conditions. Chemical reactions are not observed to occur between D+(D2O)(n) and chlorine nitrate. Instead, through studies employing the heavy isotope of hydrogen, we found that the nitric acid observed in the product ion spectrum arises from a nitric acid impurity that is usually present to some degree in the methods employed to synthesize ClONO2 reactant gas. The results from this study serve to explain other conflicting reaction mechanisms reported in the literature, and which have been discussed in the context of atmospheric chemistry.