Estimation of rate coefficients for the reactions of 3with unsaturated organic compounds for use in automated mechanism construction

Abstract

Reaction with ozone (3) is an important removal process for unsaturated volatile organic compounds (VOCs) in the atmosphere. Rate coefficients for reactions of 3with VOCs are therefore essential parameters for chemical mechanisms used in chemistry transport models. Updated and extended structure-activity relationship (SAR) methods are presented for the reactions of 3with mono- and polyunsaturated organic compounds. The methods are optimized using a preferred set of data including reactions of 3with 221 unsaturated compounds. For conjugated dialkene structures, site-specific rates are defined, and for isolated polyalkenes rates are defined for each double bond to determine the branching ratios for primary ozonide formation. The information can therefore guide the representation of the 3reactions in the next generation of explicit detailed chemical mechanisms.