Ac conductivity and dielectric properties of bulk tin phthalocyanine dichloride (SnPcCl2)

The ac conductivity, sigma(ac)(omega), has been measured for bulk tin phthalocyanine dichloride (SnPcCl2) in the form of compressed pellet with evaporated ohmic Au electrodes in a temperature range 303-403 K. Ac conductivity, sigma(ac)(omega), is found to vary as omega(s) in the frequency range 42 Hz-5 x 10(6) Hz. At low range of frequency, s < 1 and it decreases with the increase in temperature indicating a dominant hopping process. At high range of frequency, s is found to be equal to approximate to 1.09 and is temperature independent. The dielectric constant, epsilon(1), and dialectic loss, epsilon(2), have been determined for bulk SnPcCl2. Both epsilon(1)and epsilon(2) decrease with the increase in frequency and increase with the increase in temperature. The Cole-Cole types have been used to determine some parameters such as; the macroscopic relaxation time (tau(o)), the molecular relaxation time (tau), the activation energy for relaxation (E-o) and the distribution parameter (alpha). The temperature dependence of tau is expressed by a thermally activated process with the activation energy of 0.299 eV. (c) 2008 Elsevier B.V. All rights reserved.