Study of ionic conductivity in cubic ceria by the statistical moment method

We have investigated the diffusion and ionic conductivity of the cubic ceria CeO₂ using the statistical moment method (SMM) in the statistical physics. The activation energy, diffusion coefficient, pre-exponential factor and ionic conductivity are derived in closed analytic forms. The SMM calculations are performed by using the Buckingham potential for the cubic ceria. The effects of the three different potential parameter sets of the Buckingham potential and influence of dipole polarization effects on activation energy, diffusion coefficient and ionic conductivity for CeO ₂ are also investigated. The present analytical formulas including the anharmonic effects of the lattice vibrations give the predicted values of these quantities, which are comparable to those of the experimental values.