ENERGY-TRANSFER AS A FUNCTION OF COLLISION ENERGY .2.

The technique used here involves the spectroscopic study of the change in infrared liminescent intensity from a heated seeded supersonic beam of hydrogen halide molecules. HX, undergoing collisions with a secondary beam of inert gas. The change in population of individual J levels was recorded and analysed in terms of a simple exponential dependence of the rotational inelastic corss section on the amount of energy transferred between rotation and translation. The primary objective of the present study was to obtain values of the constant C that determines the magnitude of the exponent in this expression. In part I we obtained evidence for a decrease in C with increase in collision energy T - reflecting a corresponding increase in T ↔ R transition probability. In part II we give improved data for C(T) in HF-Ar, Kr, Xe collisions from T = 11-44 kcal mole-1, and C(T) in HCl-Ar, Kr collisions from T = 16-35 kcal mole-1. We also provide confirmatory evidence of fst RR resonant energy-transfer at low collisions energy, T ≈ 4 kcal mole-1, in the systems HClHF. © 1979.