Crystal structure, dielectric and magnetic properties of Ba5NdNi1.5Nb8.5O30 tungsten bronze ceramic

Ba5NdNi1.5Nb8.5O30 tungsten bronze ceramic was prepared by the conventional solid-state reaction. Rietveld analysis revealed that this ceramic crystallizes in space group p4bm. The dielectric and magnetic properties of Ba5NdNi1.5Nb8.5O30 were investigated in relation to its structure. A broad dielectric constant peak at 293 K was observed in the dielectric spectrum of Ba5NdNi1.5Nb8.5O30, suggesting a diffused normal ferroelectric transition. A modified Curie–Weiss law was used to characterize the diffuseness of the phase transition with a frequency of 1 MHz and the diffusivity γ was measured to be 1.102. The dielectric properties originate from the different crystal structures governed by the occupancy of cations at A1 and A2 sites. Ba5NdNi1.5Nb8.5O30 ceramic presents a weak antiferromagnetic interaction and the calculated effective moment is 4.77 μB/f.u.