Vibrational Relaxation of Oxygen by O2-O Collision

Abstract

: Vibrational relaxation of oxygen by O 2 -O collision is studied in the temperature range 2000-7000 K with physical kinetics and molecular collision dynamics. This study shows that all the potential energy surfaces appearing in the collision must be considered to correctly calculate rate constants, and that the Bethe-Teller theory is inadequate to describe vibrational relaxation in strong non-equilibrium, and validates widely used experimental models for vibrational relaxation.

High Fidelity Modeling of Thermal Relaxation and Dissociation of Oxygen

“…Among other collisional pairs, the interaction of molecular oxygen with the parent atom is interesting from the physical point of view due to the fast vibrational quenching [14] and a strong chemical effect [15] in the O 3 molecular system. The dynamics of O 2 -O collisions have been studied previously theoretically [11,[16][17][18][19] and experimentally [20][21][22][23][24][25]. Owing to growing computational resources, the statistical analysis of molecule-atom interaction became computationally tractable.…”

“…Owing to growing computational resources, the statistical analysis of molecule-atom interaction became computationally tractable. Particularly, the quasi-classical trajectory method (QCT) [26] was applied [11,16,17] to obtain the rates of vibrational transitions in O 2 -O collisions using an ab-initio potential energy surface (PES) [27] at temperatures observed in hypersonic flows. Recently, the kinetics of the O 2 -O molecular system was investigated by means of a system of master equations, using a database of energy transfer rates, obtained for each vibrational state [28].…”