Atmospheric chemistry of the reaction between propylene carbonate and OH radical: An ab initio RRKM-based master equation study

摘要

The kinetics of the reaction between propylene carbonate (PC) and OH radical is intensively studied using the master equation/Rice-Ramsperger-Kassel-Marcus (ME/RRKM) rate model, which includes hindered internal rotation and tunneling corrections, on the potential energy surface mapped out at the CCSD(T)/CBS//M06-2X/aug-cc-pVTZ level. Consistent with scattered literature data, the total rate constants are found to be pressure-independent and negatively temperature-dependent as k(tot)(T) = 1.27 x 10(-3) x T-3.21 x exp(-446.2 K/T) cm(3)/molecule/s in the range of 200-500 K and 10-760 Torr, in which the reaction favors at the C-alpha site to form the dominant product PC-alpha. The following unimolecular reactions of three PC radicals are also investigated.