Diffusion Coefficients of Ferrocene and Ferricinium Ion in Tetraethylammonium Perchlorate Acetonitrile Solutions, as Determined by Chronoamperometry

The diffusion coefficient of ferrocene in 0.1 mol dm−3 tetraethylammonium perchlorate acetonitrile solution at 25°C was determined by potential step chronoamperometry at a small disk electrode. And the diffusion coefficient of ferricinium ion that had been electrogenerated at the electrode was determined by double potential step chronoamperometry. The former one was (2.62 ± 0.01) × 10−9 m2 s−1 and the latter one was (2.14 ± 0.02) × 10−9 m2 s−1.