Dielectric properties of cubic bismuth based pyrochlores containing lithium and fluorine

In this work dielectric properties of Bi1.5Zn1−xLixNb1.5O7−xFx with x = 0.25 were investigated in a 20 Hz–12 GHz frequency and 120–500 K temperature range and compared to that of regular cubic BZN (when x = 0). Measurements showed that both ceramics have dipolar glass type dielectric dispersion with wide relaxation time distributions. Mean relaxation time follows Arrhenius law in the investigated frequency range, although Vogel–Fulcher law was anticipated.