Steric effects in rate constants for bimolecular dissociation

The steric effects in rate constants for bimolecular dissociation were investigated via the collision theory, and a sterically- dependent bimolecular dissociation model was established. In order to validate the developed model, the rate constants of typical reaction taken place in air under thermal equilibrium condition were then calculated based on the new model, and were compared with the results obtained by the classical collision theory, and the available experimental data. As shown by the Arrhenius plots presented in this paper, the new model would provide more accurate results than the classical collision theory when compared with the experimental data. The plots also depict some exceptional cases in the reactions of N₂+N and O₂+O, where there are discrepancies among the theoretical and experimental data. These discrepancies are also discussed in the present paper.