Three-body collision contributions to recombination and collision-induced dissociation. I. Cross sections

Many of the current chemical kinetics textbooks and kinetics papers treat atomic and molecular recombination and collision-induced dissociation (CID) as occurring only via sequences of two-body collisions. Actually, there is considerable evidence from experiment and classical trajectory calculations for contributions by true three-body collisions to the recombination of atomic and diatomic radicals, and that evidence is reviewed. Then, an approximate quantum method treating both two-body and three-body collisions simultaneously and on equal footing is used to calculate cross sections for the reaction Ne2+H⇌Ne+Ne+H. The results provide clear quantum evidence that direct three-body collisions do contribute significantly to recombination and CID.