Mobilities of Li+ in Ne and in N2 and Na+ in SF6: Effect of inelastic energy loss.

Ion mobility measurements were made for Li+ in Ne and in N2 and Na+ in SF6 using a variable-temperature drift tube. The measurements were made by two different methods: variable-E/N method at constant T and variable-T method at constant E/N, where E, N, and T are the electric field strength, the gas number density, and the gas temperature, respectively. Two datasets were compared at the same effective temperature Teff, as calculated from the Wannier equation. For Li+ in Ne, the two datasets are put on a single curve in the range 150 K<Teff<10 000 K, indicating that the scaling rule holds well. However, for Li+ in N2 and Na+ in SF6 there exists a mobility difference between the two datasets, which is attributed to inelastic energy loss in the variable-E/N measurement. Using the modified Wannier equation developed by Viehland et al., we determined the inelastic energy loss factor for Na+ in SF6. © 1996 American Institute of Physics. [ABSTRACT FROM AUTHOR]