Diffuse phase transition in Na2Pb2R2W2Ti4V4O30 (R= Gd, Eu) ferroelectric ceramics

The new complex polycrystalline samples of Na2Pb2R2W2Ti4V4O30 (R= Gd, Eu) were prepared by a low temperature (∼700∘C) solid-state reaction technique. Preliminary X-ray diffraction (XRD) studies of the compounds showed the formation of single-phase orthorhombic crystal structure at room temperature. Studies of dielectric properties (ε, tanδ) of the above compounds at frequencies 1, 10, 100 and 1000 kHz in a wide temperature range (300-700 K) exhibit the ferroelectric phase transitions of diffuse type.