ENERGY-DEPENDENCE OF COLLISION CHARACTERISTICS IN MOLECULE SURFACE COLLISIONS

For a model diatomic molecule-surface collision, we show that the extent of chaoticity, as evidenced in action-angle and lifetime plots, decreases dramatically with an increase in the translational energy of the molecule. In addition to the existence of a threshold for the dissociative chemisorption, there is also an antithreshold at higher energies. The implications for the existence (or lack thereof) of chaos/fractals in molecule-surface collisions are also discussed, particularly as related to translational-vibrational energy redistribution.