Synthesis and characterisation of orthophosphate KPbPO4 compound

KPbPO4 compound was prepared by the conventional solid-state method. The phase formation of the compound was checked by X-ray diffraction powder (XRD). The compound crystallizes in the orthorhombic system with the following crystal data: Pnma, Z = 4, (a = 7.450 (1) Å, b = 5.635 (7) Å, c = 9.958 (7) Å and V = 418.120 (1) Å3). Arcanite structure was formed by regular PO43−tetrahedra surrounding the Pb1|K1 and Pb2|K2 cations in nine and eight coordinations, respectively. Besides, the electrical data analysis of the impedance spectra was adapted to an equivalent circuit. Furthermore, the alternating current (AC) conductivity of grain contribution was interpreted by using the universal Jonscher's power law, and the frequency exponent n was studied for the compoundʹs conduction. The non-overlapping small polaron tunneling model (NSPT) was proposed as a closely good model to describe the conduction mechanism.