Ion dynamics in superionic chalcogenide glasses: Complete conductivity spectra

The complete conductivity spectra of the glass 0.5Ag(2)S-0.5GeS(2) were obtained in very broad temperature and frequency ranges. The experimental data were analysed in two different ways. First, the classical and well known power law procedure was used. For this glass, the conductivity is described by the superposition of four terms. The first two terms are thermally activated, whereas the last two terms are almost temperature independent. The second data analysis is based upon the master curve procedure: the experimental data could be described only by the superposition of the master curve and the vibrational contribution. This procedure seems to be less arbitrary than the first one because the master curve can be generated without any fitted parameter and certainly displays the common origin of the microscopic processes involved. (C) 2000 Elsevier Science B.V. All rights reserved.