Exhaustive State-to-State Cross Sections and Rate Coefficients for Inelastic N-N Collisions using QCT Combined with Neural Network Models.

Using the quasi-classical trajectory method, we systematically studied the state-to-state vibrational relaxation process of N() + N() collisions over a wide temperature range (5000-30,000 K). Different temperature dependencies of the single- and multiquantum VV and VT events in various (,) collisions are captured, with the dominant channel being related to the initial vibrational energy levels ( = 50). At a specified relative translational energy, there is a monotonic relationship of the VT cross sections with the vibrational energy level, particularly in high-energy collisions.

Dissociation cross sections and rates in O + N collisions: molecular dynamics simulations combined with machine learning.

The collision-induced dissociation reaction of O (, ) + N, a fundamental process in nonequilibrium air flows around reentry vehicles, has been studied systematically by applying molecular dynamics simulations on the ', ' and ' potential energy surfaces of NO in a wide temperature range. In particular, we have directly investigated the role of the ' surface in this process and discussed the applicability of the simplified approximate rate models proposed by Esposito and Andrienko based on the lowest two surfaces. The present work indicates that the state-selected dissociation of O + N is dominated by the ' surface for all except for the low-lying O states.