Studies of electric, dielectric, and conduction mechanism of LiNiV0.5P0.5O4

The LiNiV_0.5P_0.5O₄ compound is prepared using a solid-state reaction method. The X-ray diffraction studied and found to be an orthorhombic system and Pnma space group. The spectra follow the Arrhenius law with two activation energy the first in the region of temperatures before 621 K (Region I) and the second in the region after 621 K (Region II). An agreement between the experimental and theoretical results are discussed and it is suggested that the ac conductivity can be explained by the correlated barrier hopping (CBH) and non-overlapping small polaron tunneling model (NSPT) in region I and II, respectively. Moreover, the value of activation energy for the bulk obtained from the analysis of equivalent circuit and modulus relaxation confirms that the transport is not due to a simple hopping mechanism and that the ion transport is probably due to the hopping of Li⁺ ions.