Electric conductivity and relaxation in ZnF2–AlF3–PbF2–LiF glasses

The electric conductivity of ZnF2–AlF3–PbF2–LiF glasses has been studied in the frequency range 10 Hz–2 MHz and in the temperature range from 300 K to just below the glass transition temperature. The conductivity decreases with the increase in the LiF content in the composition, which results from the trapping of F− ions by Li+ ions. Small values of the stretching exponent β are observed for the present glasses. The value of the decoupling index decreases with an increase in LiF content, consistent with the composition dependence of the conductivity.