Dynamics with a Rotational Transition State

摘要

Rotationally inelastic collisions between hydrogen molecules and polar molecules, especially water, are of great importance in assessing the thermodynamic properties of interstellar gases. We show here on a simple model that momentum exchange is efficiently mediated by a relative transition state. It acts as a threshold between an inner region and an outer region around the polar molecule. The geometric properties of classical dynamics at threshold are discussed and a capture type of theory is described.