Structure and relaxation of relaxor ferroelectrics

The Pb-based complex relaxor ferroelectrics(RFE) of PMN and PZN ceramics were prepared.The microdomain-macrodomain transition of relaxor ferroelectrics was studied by using amending local freezing glass-model.The frequency dispersion of the temperature of the dielectric permittivity maximum had been caused by the structural fluctuation of RFE during the microdomainmacrodomain transition.The more the structural fluctuation of RFE was,the lower the relaxation degree was in the process of microdomain-macrodomain transition.The relaxation degree was diminished or vanished when the microdomain became larger.