TERMINATION OF COMPUTER-GENERATED REACTION-MECHANISMS - SPECIES RANK-BASED CONVERGENCE CRITERION

The issue of the termination or truncation of computer-generated react ion models is addressed. The product rank of each species, a quantitat ive measure of the order in which a product appears in a reaction mech anism, was tallied during generation of the reaction mechanism. Incorp oration of product rank in the convergence criterion allowed generatio n of reaction mechanisms for reactants and conditions that previously exhausted available memory when only the maximum carbon count was spec ified. A rank-based convergence criterion alone resulted in generation of infinite reaction mechanisms when radical addition reactions were considered. The rank-based criterion combined with an upper bound on t he atom count of radical species capped the number of addition reactio ns that occurred. Coupling these two criteria provided the best capabi lity for predicting reactant conversion and major and minor product yi elds with the fewest number of excess components. Inherently convergen t reaction networks require no external convergence criteria..