Accurate reaction barriers and rate constants of H-abstraction from primary, secondary, and tertiary amines by H atom determined with the isodesmic reaction method

Abstract The H-abstraction reaction kinetics of primary, secondary and tertiary amines with H atom are computed using the isodesmic reaction method. The average unsigned deviation of energy barriers is 12.40 kcal mol-1 at the HF/6-31+G(d) level compared to the CCSD(T)/CBS(D-T-Q) method but reduced to 0.75 kcal mol-1 after corrections. The calculated rate constants of all reactions and corresponding rate rules are also presented. This work solves the accurate energy barrier calculations for larger molecules reaction amines + H at a low level HF method and also provides the accurate reaction kinetics for the critical important H-abstraction reactions of amines combustion modeling.