The conductivities of solid solutions which contained 10mol% of a rare-earth oxide were measured (table 213) in order to determine the form of the temperature variation. It was found that the Arrhenius plots were broken straight lines, with a number of linear sections which depended upon the nature of the added ion. There was a decrease in the number of linear segments, and a shift of the low-temperature break towards higher temperatures, as the radius and polarizability of the rare-earth ion increased. This behavior was attributed to a change in the electrostatic potential, that occurred at an anion site due to a change in the average interionic distance, and to a change in the contribution which the ion-dipole interaction made to the potential energy of the anion (see entries for ZrO2-Gd2O3, ZrO2-Lu2O3, ZrO2-Nd2O3, ZrO2-Sc2O3, ZrO2-Y2O3 and ZrO2-Yb2O3).

A.N.Vlasov: Elektrokhimiya, 1989, 25[5], 699-702

Table 213

Ionic Conduction Parameters for ZrO2-10mol%Ho2O3

Ho: ionic radius = 0.0901, polarizability = 0.0016

Table 214

Ionic Conduction Parameters for ZrO2-10mol%Lu2O3

Ho: ionic radius = 0.0861, polarizability = 0.0013