Vibrational energy transfer and collision-induced dissociation in O + O₂ collisions

This paper presents molecular dynamics calculations of vibrational energy transfer and nonequilibrium dissociation in O₂ + O collisions. The O₂ + O interactions are modeled using nine potential energy surfaces corresponding to the 1¹A', 2¹A', 1¹A' 0, 1³A', 2³A', 1³A", 1⁵A', 2⁵A', and 1⁵A" states, which govern electronically adiabatic collisions of ground-electronic-state collisions of diatomic oxygen with atomic oxygen. Characteristic vibrational excitation times are calculated over a temperature range of T = 3000 K to T = 15,000 K, and nonequilibrium dissociation rate coefficients are calculated over a temperature range of T = 6000 K to T = 15,000 K. Vibrational relaxation rates, specific to each PES, are found to vary by over an order of magnitude, indicating that all spin couplings and spatial degeneracies must be considered for accurate predictions of O₂ + O collisions. It has been observed that the characteristic vibrational excitation time for O₂ + O interactions is weakly dependent on temperature and increases slightly with increasing temperature. Predicted nonequilibrium dissociation rates, during quasi-steady state. Agree well with available experimental data, and the coupling between vibrational energy and dissociation is characterized.