Alkoxyl radical decomposition explained by a valence-bond model

Recent structure-activity relationships (SAR) have been proposed to estimat e the kinetic parameters of the decomposition reaction of alkoxyl radicals, which are important intermediates in the tropospheric degradation of volat ile organic compounds. In this paper, we propose an interpretation of these relationships based on chemical and structural arguments supported by a va lence-bond (VB) model. The interest of such an analysis is to demonstrate i ts generality since it is independent of the quantum chemistry method used to perform calculations provided that this method describes correctly the c hange of the electronic structure along the decomposition path.