Temperature Dependence of Ionic Mobilities in Gas Mixtures

Abstract

An ion mobility tube has been used to investigate the mobilities of various ions in helium—neon mixtures at gas temperatures of 77°, 195°, and 300°K. From plots of reciprocal mobility vs fractional concentration of the gases in the mixture which exhibit the linear dependence predicted by Blanc's law, it is possible to trace the mobility of a given ion, e.g., He⁺, from its parent gas (helium) value, through the mixtures, to its value in the ``foreign'' gas (neon). In this way we have determined the thermal‐energy mobilities of the various ions under conditions where the ion—atom interaction changes markedly (e.g., from predominantly charge transfer to polarization interaction). In addition, a search was made for the effects of (HeNe)⁺, previously postulated to account for deviations from Blanc's law in 300°K studies. No effects clearly attributable to (HeNe)⁺ ions have been observed.