Reaction of NO3 and N2O5 with Molecular Species of Possible Atmospheric Interest

Article abstract of DOI:10.1021/j100307a040

The nitrate radical (NO3) has been shown to play an important role in nighttime tropospheric chemistry, particularly in polluted atmospheres.In order to understand more fully the role of NO3 in loss processes for various atmospheric species, a number of laboratory kinetic studies have been undertaken.Reported here are rate constant upper limits for the reaction of NO3 and N2O5 with HCl, ClNO, H2S, NH3, N2O, CH3CN, and CH4.Chemical reaction was observed in several of these systems (HCl, ClNO, H2S, and NH3), but possible heterogeneous (wall-catalyzed) reactions cannot be excluded.Possible mechanisms are presented for those cases where reaction occurred.In addition, studies of the reactions HCl + NO2, H2S + NO2, and Cl + HNO3 are also reported.The upper limits reported here rule out the reactions of NO3 or N2O5 in the gas phase as important removal processes for these species, but it is possible that the reaction of HCl with N2O5 catalyzed by aerosol surfaces may play an important role in linking the chemistry of the stratospheric odd nitrogen and odd chlorine cycles.