Electrical properties, equivalent circuit and dielectric relaxation studies of [(C₃H₇)₄N]₃Bi₃Cl₁₂ compound

Abstract

The tri-tetrapropylammonium dodeca chlorobismuthate(III) has been characterized by differential scanning calorimetry (DSC), X-ray powder and impedance spectroscopy. DSC analysis and X-ray diffraction as function of temperature have revealed one irreversible solid–solid phase transition at 414 ± 5 K of order–disorder types. The electrical properties were studied using impedance spectroscopy at different temperatures in the frequency range of 209 Hz–5 MHz. The obtained results were analyzed by fitting the experimental data with the equivalent electrical circuit. We observed that the temperature dependence of the electrical conductivity of materials exhibits a crossover from T ^−1/4 to T ⁻¹ dependence in the temperature range between 414 and 453 K. Furthermore, the modulus plots can be characterized by the non-experiential decay function $\varphi \left( t \right) = \exp \left( {\frac{{\text{ - }t}}{\tau }} \right)^{\beta }$. The analysis of the experimental data based on the jump relaxation model has shown that the translation motion of the charge carrier and reorientation hopping between the equivalent sites of the metal chloride [Bi₃Cl₁₂]³⁻ anions and the [(C₃H₇)₄N]⁺ cations are responsible for the observed ac conductivity.