Kinetics of the Hydrogen Abstraction PAH + •OH → PAH Radical + H2O Reaction Class: An Application of the Reaction Class Transition State Theory (RC-TST) and Structure–Activity Relationship (SAR)

A reaction class transition state theory (RC-TST) augmented with structure–activity relationship (SAR) methodology is applied to predict high-pressure limit thermal rate constants for hydrogen abstraction by • OH radical from polycyclic aromatic hydrocarbons (PAHs) reaction class in the temperature range of 300–3000 K. The rate constants for the reference reaction of C 6 H 6 + • OH → C 6 H 5 + H 2 O is calculated by the canonical variational transition state theory (CVT) with small curvature tunneling (SCT). Only the reaction energy is needed to predict RC-TST rates for other processes within the family, the parameters needed were obtained from M06-2X/cc-pVTZ data for a training set of 34 reactions. The systematic error of the resulting RC-TST rates is smaller than 50% in comparison with explicit rate calculations, which facilitates application of the proposed methodology to the automated reaction mechanism generators (ARMGs) schemes.