Electrical and dielectric properties of MnF2-ZnF2-NaPO3 glasses

Direct electrical conductivity and dependencies of complex electrical modulus vs. temperature and frequency have been measured on glasses from the MnF2-ZnF2-NaPO3 system. These glasses are sensitive to atmospheric humidity and as a consequence, the electrical conductivity increases up to temperature of 50 degrees C. A hydrated layer is created by the effect of water and leads to the significant increase of the electrical conductivity in the case of 0MnF(2)-20ZnF(2)-80NaPO(3) glass. This behavior is governed by Arrhenius relation where the values of activation energy are increasing and values of the electrical conductivity are decreasing with the amount of MnF2. Dielectric measurements show that a heterogeneous phase is formed in the bulk of glasses. This may be seen when plotting complex electrical modulus in the complex plane. The records made by the light microscope confirmed the occurrence of the other phase in the bulk of glasses. (C) 2009 Elsevier B.V. All rights reserved.