Structural, magnetic, and dielectric studies on rare earth substituted bismuth titanate Bi2R2Ti3O12 (R = Nd, Sm, Eu, Gd)

The effects of rare earth ion substitution on the structural and physical properties of ferroelectric Bi4Ti3O12 were studied. Polycrystals of rare earth ion substituted bismuth titanate Bi2R2Ti3O12 with R = Nd, Sm, Eu, Gd were prepared by conventional solid state reaction. Magnetization measurements revealed that orbital moment quenching of the rare earth ions occurs in this group of compounds and that all the compounds remain paramagnetic even at low temperatures despite the presence of underlying antiferromagnetic couplings. Rare earth ion substitution also suppresses the ferroelectricity.