Criegee intermediates (CIs) are important zwitterionic oxidants in the atmosphere, which affect the budget of OH radicals, amines, alcohols, organic/inorganic acids, etc. In this study, quantum chemical calculation and Born-Oppenheimer molecular dynamic (BOMD) simulation were performed to show the reaction mechanisms of C2 CIs with glycolic acid sulfate (GAS) at the gas-phase and gas-liquid interface, respectively. The results indicate that CIs can react with COOH and OSO3H groups of GAS and generate hydroperoxide products. Intramolecular proton transfer reactions occurred in the simulations. Moreover, GAS acts as a proton donor and participates in the hydration of CIs, during which the intramolecular proton transfer also occurs. As GAS widely exists in atmospheric particulate matter, the reaction with GAS is one of the sink pathways of CIs in areas polluted by particulate matter.
Keywords: Criegee intermediates; aqueous-surface reaction; gas-phase reaction; glycolic acid sulfate; proton transfer.