Automated mechanism generation. Part 1: mechanism development and rate constant estimation for VOC chemistry in the atmosphere

A framework for automated mechanism generation for modeling atmospheric chemistry at the mechanistic level was developed. In part 1, categorization of reactions into reaction families and determination of rate coefficients using a hierarchical approach that uses experimental data and kinetic correlations are described. The main focus was to develop kinetic correlations for estimating rate coefficients that are not available experimentally, and the main correlation used was the Evans–Polanyi relationship that relates the activation energy to the heat of reaction. A hierarchical scheme for calculating heats of reaction and other thermodynamic properties was developed. The rate constants calculated using the proposed correlations are in most cases within an order of magnitude of available experimental values, and 82% are within a factor of five.