Mobility and diffusion of lithium ions in neon

Abstract

The mobility and the transverse diffusion coefficient have been measured for 7Li+ ions in neon at 295 K and field-to-density values E/n0 up to 200 Td. The experimental transport coefficients were compared with values calculated from a recent ab initio potential (Roeggen et al. 1991). The calculated mobilities were 0.5% higher than the experimental mobilities at low fields, and 1.8% lower at high fields. Slight adjustments to the ab initio potential (essentially a shift of the repulsive branch by 0.02 a0) were sufficient to reduce this difference to +or-0.3% or less at all values of E/n0. The long-range part of the 'mobility-modified potential' corresponds to a polarizability for the neon atom alpha =2.682 au. This is about 0.5% above other 'experimental values', and about 0.5% below recent theoretical values.