REACTION OF CHLORINE NITRATE WITH PROTONATED WATER CLUSTERS - A MODEL FOR HETEROGENEOUS REACTIONS ON POLAR STRATOSPHERIC CLOUDS

We investigated the reactions of small protonated water clusters, H3O+(H2O)n, with chlorine nitrate, ClONO2, to elucidate the molecular mechanism for the heterogeneous reaction of chlorine nitrate with ice. The ionic reaction products were various forms of protonated nitric acid, NO2+(H2O)m, m = 0, 1, 2. These products are analogous to products previously reported in the literature for the neutral reaction occurring on ice surfaces. Our results support the hypothesis that the heterogeneous reaction is acid-catalyzed.