The influence of phase probability distributions on impedance spectroscopy

Abstract

The brick layer model is normally employed in impedance spectroscopy calculations whenthe material system is homogeneous. Here, we use probability distributions to modify thismodel for real inhomogeneous materials. In the plot of Z' against Z''/f we find that the straight lines change into curves for inhomogeneous phases. We can alsodistinguish between the effects of overlap and the effects of distribution from the shape ofthe plot. By fitting the impedance spectra, we can evaluate the degree of homogeneity ofthe phase. Analysis of a negative temperature coefficient ceramic shows that the new modelcan fit real experimental data very well.