A theoretical study of the reactions of parent and substituted Criegee intermediates with water and the water dimer

A theoretical study was performed involving the reactions of a series of atmospherically significant Criegee intermediates (CIs), including parent, mono- and dimethyl-substituted CIs, with water and the water dimer at the CCSD(T)//B3LYP/6-311+G(2d,2p) level. We investigated two reaction routes leading to alpha-hydroxyalkyl hydroperoxide (HAHP). According to our calculations, the most favorable route is the formation of HAHP as the result of reactions of CIs with the water dimer. The rate constants for both pathways were calculated and the dependence of overall rate constant on temperature and relative humidity was also evaluated. The implication of our results to the chemistry of the troposphere is herein discussed.