Relaxor-like dielectric relaxation: artifacts and intrinsic properties

The existing results on the relaxor-like dielectric behavior which is characterized by a broad maximum in a dielectric permittivity as a function of temperature and the low frequency dielectric dispersion are reviewed for different ferroelectric and non-ferroelectric materials. The general and distinctive features of the relaxor and relaxor-like dielectric anomalies are discussed. Brief discussion of the existing treatments of dielectric data, which take into account not only, the bulk properties of the materials but also the interfacial effects is given. New model explaining the relaxor-like response on the base of the association-dissociation theory of impurity dipole complexes is proposed.