Vibrational Relaxation of Diatomic Molecules

Abstract

A one-dimensional model is explored and rigorous solutions are obtained to the classical equations of motion yielding transition probabilities between low-lying vibrational levels of diatomic molecules. Results are listed for four halogens, O2, N2, and CO colliding in pure gases and O2 with Ar or He as a collision partner. Selecting a single variable ``a'' (the range term of the Morse potential function), excellent agreement was found with the available experimental data over a 30-fold temperature range. The validity of the Landau—Teller theory is discussed; in particular, the effect of the consideration of an attractive potential and the simplification involved in its explicit treatment. Transitions involving double quantum jumps are considered. Some preliminary results of a two-dimensional model are discussed.