Diffusion coefficients and interaction potential for Na + ions in argon gas

Abstract

Experimental values of the ratio, D T/K, of the transverse diffusion coefficient to mobility for Na + ions drifting in Ar gas have been determined with greater accuracy and at higher E/N (electric field to neutral gas density ratio) regions than previously. Results at a drift tube temperature of about 303 K are reported with estimated accuracies of +or-3% at E/N values ranging from 5 to 500 Td. Furthermore, the reduced mobility, K 0, And the ratios D T,L/K of the transverse and longitudinal diffusion coefficients respectively to mobility, were calculated using Monte Carlo simulations (MCS). Comparisons between the experimental values of D T/K and those calculated using the interaction potential of Koutselos, Mason and Viehland (1990) suggest that this interaction is a good representation of the true potential in the long and intermediate ranges. © 1994 IOP Publishing Ltd.