A new OH vibrational distribution model developed using molecular dynamics

Abstract

A semi-classical molecular dynamics approach is used to model the dissociation of water to form the hydroxyl radical. The unimolecular dissociation of water is used to calculate the probability of reaction as well as determine the product OH translational, vibrational, and rotational energy distributions. The molecular dynamics probabilities of reactions and product distributions are used in the direct simulation Monte Carlo method to model spatial distribution and temperatures of OH in the bow-shock of a 5 km/sec vehicle at 80 and 100 km. Ultraviolet spectra of the OH(X→A) transition are computed and compared with data from the Bow Shock Ultraviolet Flight Experiment 2. Excellent agreement of the spectral features between theory and experiment is obtained.