An empirical relation between the limiting ionic molar conductivities and self-diffusion coefficients of pure solvents

Abstract The limiting ionic molar conductivity ( λ ∞ ) of an electrolyte solution depends on the self-diffusion coefficient ( D s ) of the pure solvent when the temperature ( T ) changes. To study the D s -dependence of λ ∞ , we proposed a new empirical relation λ ∞ ∝ ( D s / T ) t , with a parameter t . The relation is applied to the λ ∞ and D s of alkali, tetra-alkyl ammonium, and halogen ions in water or methanol. All ions except for tetra-alkyl ammonium ions in water exhibit excellent linear relationships in their λ ∞ ∝ ( D s / T ) t plots, with t in the range from 0.88 to 1.26. This is the first report showing an affirmative linear correlation between λ ∞ and D s .