Molecular dynamics study of dimer formation

Abstract

Molecular dynamics studies have been conducted with a dilute atomic gas interacting with the Lennard‐Jones (6–12) potential. Previously dimers, two particle‐bound states, have been shown to form in these finite two‐dimensional models. The dimer mole fraction is determined for nine systems with different temperatures and density and is found to agree with the theoretical dependences predicted by Stogryn and Hirschfelder. These results are also shown to be consistent with experimental measurements by Milne and Greene and by Leckenby and Robbins. The reaction rate constant, K₃, for the formation of argon dimers was observed to vary as T^−1/3 and be independent of density. The steric factor for formation of dimers varies from 0.07 to 0.18 in the temperature range considered.