Theoretical studies on the reactions of acetone with chlorine atom and methyl radical

Theoretical investigations are carried out on the reaction multi-channel CH₃COCH₃ + Cl (R1) and CH₃ COCH₃ + CH₃ (R2) by means of direct dynamics methods. The minimum energy path (MEP) is obtained at the MP2/6-31 + G(d,p) level, and energetic information is further refined at the BMC-CCSD (single-point) level. The rate constants are calculated by the improved canonical variational transition state theory (ICVT) with the small-curvature tunneling (SCT) correction in a wide temperature range 200-3,000 K. The theoretical overall rate constants are in good agreement with the available experimental data and are found to be k ₁ = 3.08 × 10^-17 T ^2.03exp(-32.96/T) and k ₂ = 1.61 × 10^-23 T ^3.53 exp(-3969.51/T) cm ³molecule^-1s^-1.