Divide line between relaxor, diffused ferroelectric, ferroelectric and dielectric

The dielectric spectroscopic studies of relaxor ferroelectric Ba(Ti0.70Sn0.30)O3 (BTS30), diffused ferroelectric Ba(Ti0.70Sn0.20)O3 (BTS20), classical ferroelectric BaTiO3 (BT0), and normal dielectric Ba(Fe0.50Ta0.50O3) (BFT) were carried out in the temperatures ∼100 K–650 K, and frequencies ∼100 Hz–1 MHz, which showed relaxor behavior at 130 K with typical 30 K frequency dispersion, perfect diffused ferroelectric character at 190 K, classical ferroelectric, and dielectric relaxation at 450 K–550 K respectively. A divide line was sketched between the relaxors, ferroelectrics and normal dielectrics based on the Maxwell–Wagner space charge model. The impedance spectroscopy and ac conductivity spectroscopy were carried out to explain the relaxor and pseudo relaxor behavior.