Limits of Applicability of the Treanor–Marrone Model for State-Specific Dissociation Rate Coefficients of N2 and O2

Modern scientific and technology challenges reveal the necessity for studying strongly non-equilibrium flows. For the modelling of non-equilibrium chemical-vibrational kinetics, data on the dissociation rate coefficients are required. Several types of models for dissociation rates exist in the literature: theoretical, experimental models as well of those based on the quantum chemistry methods. These approaches differ by computational complexity and accuracy of the results. This paper is devoted to refining the models of dissociation rate coefficients for problems of state-specific kinetics. Behavior of the dissociation rate coefficients in binary mixtures (N2, N) and (O2, O) has been studied. Two main approaches to determine the dissociation rate coefficients: the semi-empirical theoretical Treanor–Marrone model and trajectory calculations based on the quasi-classical methods (QST) have been compared. The parametric theoretical model is characterized by sufficient computational simplicity, while the QST methods provide accurate results. Based on the comparison of dissociation rate coefficients obtained by different approaches, the existence of the Treanor–Marrone model parameter, yielding the results equivalent to the results of trajectory calculations has been studied. Recommendations for the optimal choice of the parameter as a function of temperature and vibrational energy have been given.