Theoretical studies of the reactions of methyl radical with dimethyl ether and 1,2-ethanediol

Rate coefficients for the CH3OCH3 + CH3 reaction (RA) and the (CH2OH)2 + CH3 reaction (RB). [Display omitted] •The tunneling and variational effects are important for the H-abstraction channels.•The H-abstraction channel from the CH3 group is the dominant channel in the CH3OCH3 + CH3 reaction.•The H-abstraction from CH2 group is predominant less than 1100 K in the (CH2OH)2 + CH3 reaction. The CH3OCH3 + CH3 and (CH2OH)2 + CH3 reactions were characterized using CCSD(T)/CBS//M06-2x/cc-pVTZ theory. For the two reactions, a total of five reaction channels have been described, including the H-abstraction channels. The rate coefficients were calculated by CVT/SCT and the fitting parameters of Arrhensive formulas were given. The calculated rate coefficients agreed well with the available reference values. Note that the H-abstraction channel is the dominant channel over almost the calculated temperature range for the CH3OCH3 + CH3 reaction. The H-abstraction from CH2 group is predominant less than 1100 K and the the H-abstraction from the OH group become important higher than 1200 K in the (CH2OH)2 + CH3 reaction.