Frequency Dispersion in Capacity Measurements at a Disk Electrode

The geometry of an electrode system affects the frequency dispersion of impedance measurements if the primary current distribution on the electrode is nonuniform. This effect is treated for a disk electrode embedded in an insulating plane with the counterelectrode at infinity. The apparent capacity is found to approach zero at large frequencies. The frequency dependence of the apparent capacity will be much smaller for a spherical electrode tangent to an insulating plane. The latter system is also treated briefly.