Statistical Model for the Vibrational Deactivation of Molecular by Atomic Oxygen

A theoretical investigation is performed of the transfer of vibrational energy from a highly excited diatomic molecule to a free atom at thermal velocities under the special condition of a deep attractive minimum in the intermolecular potential. The model utilizes a Monte Carlo statistical analysis of classical particle trajectories, with calculations performed for selected semiempirical forms of the interaction potential. Data relevant to the ozone stable configuration are applied to the O–O2 system, with primary emphasis upon the role of the latter in atmospheric reactions which produce the OH airglow emission. A deep attractive potential well is found to be the principal parameter leading to rapid vibrational deactivation of O2, with cross sections of the same order as kinetic cross sections and with the direct collision process of an importance comparable to the atom-interchange mechanism. The fundamental concept of the “intermediate complex” is favored to best describe the details of similar reaction processes which are associated with such strong attractive forces.