Structural, electrical, leakage current, and magnetic characteristics of double perovskite Nd2NiTiO6

This study investigates the structural, electrical, leakage current, and magnetic characteristics of the double perovskite material Nd₂NiTiO₆ synthesized through the sol–gel citrate auto-ignition method. The Rietveld refinement of the X-ray diffraction patterns confirmed a monoclinic symmetry (space group P2₁/n) with an ordered arrangement of alternate NiO₆ and TiO₆ octahedra. Impedance spectroscopic analysis exhibited the material's non–Debye-type relaxation mechanism and semi-conductive nature. AC conduction analysis revealed that the conduction of charge carriers occurs via the nonoverlapping small polaron hopping mechanism, consistent with Mott's variable range hopping model. Temperature- and frequency-dependent dielectric measurements were interpreted using the Maxwell–Wagner interfacial polarization model. The analysis of thermal- and field-dependent leakage currents established that conduction is ohmic, which the Schottky barrier model explains. Studies on magnetization ruled out the presence of magnetic ordering connected to indirect interaction between Ni²⁺ ions via Ti⁴⁺ ions and the rare-earth cation (Nd³⁺) moment.