Structural, dielectric and transport properties of Pb(Mno.5Wo.5)O3

Polycrystalline Pb(Mn0.5W0.5)O3, a ferroelectric oxide having perovskite structure, was prepared by high temperature solid state reaction technique. Preliminary X-ray diffraction analysis confirms single phase formation with the lattice parametersa = 7.2501 A,b = 8.1276 A andc = 12.0232 A. Room temperature dielectric constant (e′) and loss tangent (tan δ) were scanned with respect to frequency in the range 100 Hz-1 MHz. Detailed study of dielectric constant and electrical conductivity reveals a phase change around 400 K, which is quite different from those in the other materials of the same type. Further, the seebeck coefficient (α) is temperature independent. The conduction is interpreted as due to small polaron hopping.