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arXiv · 2512.09545

A State-Space-View of Atom-Diatom Reactions Relevant to Rarefied Gas Flow

Abhirami Vijayakumar·Raidel Martin-Barrios·Markus Meuwly
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Abstract

A microscopically resolved picture of energy flow in atom-diatom collisions is essential for understanding the non-equilibrium chemistry in rarefied and hypersonic gas flow. Here, a comprehensive ensemble of quasi-classical trajectories on global, reactive, and ``vetted'' potential energy surfaces are employed to construct state-resolved probability maps and to determine the dependence of the outcomes on the initial ro-vibrational states $(v,j)$. The full range of processes, including elastic, inelastic, atom exchange, reactive, and atomization are quantified, revealing distinct structure reactivity relationships. For the [OOO] system consistent trends are obtained from two high-quality potential energy surfaces, despite their different electronic structure and representation techniques. The resulting state-space description provides a comprehensive picture of energy redistribution in high-energy atom-diatom collisions, forming a basis for improved modeling of non-equilibrium chemistry in hypersonic and rarefied environments.

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Abhirami Vijayakumar, Raidel Martin-Barrios, Markus Meuwly. 2025-12-10. A State-Space-View of Atom-Diatom Reactions Relevant to Rarefied Gas Flow. https://arxiv.org/abs/2512.09545

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