Electric Relaxational Effects Induced by Ionic Conductivity in Dielectric Materials

Abstract

The paper shows how the direct current ionic conductivity (σDC) and the static dielectric permittivity (εs) reveal themselves in the complex impedance, the electric modulus, and the conductance of molecular liquids when the frequency of the electric stimulus is much lower than that corresponding to the dipolar reorientational relaxation of the liquid under investigation. It was shown that, in such static dielectric conditions, one observes the relaxational behavior of the impedance and the electric modulus, both of the Debye-type and of the same relaxation time, depending on σDC and εs values. The discussion is illustrated with the experimental electric spectra of liquid cyclobutanone recorded in the frequency region from 500 Hz to 5 MHz and in the temperature range from 243 to 313 K.