Atmospheric Chemistry of Dimethyl Carbonate: Reaction with OH Radicals, UV Spectra of CH3OC(O)OCH2 and CH3OC(O)OCH2O2 Radicals, Reactions of CH3OC(O)OCH2O2 with NO and NO2, and Fate of CH3OC(O)OCH2O Radicals

A flash photolysis−resonance fluorescence technique was used to study the rate constant for the reaction of OH radicals with dimethyl carbonate over the temperature range 252−370 K. The rate constant exhibited a weak temperature dependence, increasing at both low and high temperature from a minimum value of approximately 3.1 × 10-13 cm3 molecule-1 s-1 near room temperature. Pulse radiolysis/transient UV absorption techniques were used to study the ultraviolet absorption spectra and kinetics of CH3OC(O)OCH2 and CH3OC(O)CH2O2 radicals at 296 K. Absorption cross sections of CH3OC(O)OCH2 and CH3OC(O)OCH2O2 at 250 nm were (3.16 ± 0.34) × 10-18 and (3.04 ± 0.43) × 10-18 cm2 molecule-1, respectively. Rate constants measured for the self-reactions of CH3OC(O)OCH2 and CH3OC(O)OCH2O2 radicals and reactions of CH3OC(O)OCH2O2 radicals with NO and NO2 were (5.6 ± 1.1) × 10-11, (1.27 ± 0.21) × 10-11, (1.2 ± 0.2) × 10-11, and (1.2 ± 0.2) × 10-11 cm3 molecule-1 s-1, respectively. The rate constant for reaction of F atoms...