A study of the effect of correlated ion motion on the electrical condu
ctivity relaxation in single-crystalline yttria-stabilized zirconia is
presented. Complex admittance in the radio frequency range show power
-law dependencies in the real part of the conductivity at high frequen
cies of the form omega(n) and asymmetric electric modulus plots as a r
esult of correlations. An analysis of the frequency dependence of the
electric modulus is conducted to obtain time decay functions of the fo
rm exp[-(t/tau)(beta)] from an analytical distribution of relaxation t
imes. Correlation times, and parameters n and beta characterizing the
relaxation in time and frequency domains are compared to show the equi
valence of time and frequency representations. The common origin of ac
and dc processes is discussed in view of the frequency dependence of
the complex conductivity. From a macroscopic activation energy for ion
motion E = 1.16 eV and a beta value of 0.43, a single-ion microscopic
activation energy E(a) = 0.5 eV is obtained as beta E according to Ng
ai's coupling model. The microscopic activation energy is related to t
he association energy of oxygen vacancies.