Termolecular and saturated termolecular kinetics for Li+ and F−

Abstract

The termolecular association of Li+ with nineteen molecules was observed in helium at 0.3–1.0 torr. The molecules included N2, CO2, SO2, NH3, substituted methanes, and substituted ethylenes. The rates ranged from 8(−31) to 5(−27) cm6 molecule−2 sec−1. Six molecules were observed to have a transition from termolecular to saturated termolecular kinetics in the 0.3 to 1.0 torr pressure range and C4F8, C2Cl2F4, and C2F6 were saturated termolecular at 0.2 torr in both helium and argon buffer and their rate constants were independent of buffer. Some qualitative comparisons are made on the Li+ association data. The F− associations with NH3, CO2, and SO2 were measured and the large rate for CO2 and SO2 indicates covalent bonding in these compounds. The over-all importance of such measurements as a ``tunable'' probe of kinetics is emphasized.