It was recalled that, in investigations of the isothermal transport properties of mixed conductors, the dynamic coupling between ionic and electronic partial fluxes was usually neglected. Within the formalism of linear irreversible thermodynamics, this assumption was reflected by a vanishing cross-coefficient, L12, in the matrix of phenomenological transport coefficients. By analyzing the phenomenological flux equations for cation vacancies and electron holes, methods for the determination of the cross-coefficient were defined. Experimental results were presented for the coupling effect in CoO. These were obtained by using 3 independent techniques. It was shown that a strong coupling between cation vacancies and electron holes existed in the case of CoO. In order to account for this coupling, an effective charge number of ions had to be introduced for use in ionic fluxes.

J.Janek: Berichte der Bunsengesellschaft für Physikalische Chemie, 1994, 98[10], 1213-23