Low-frequency dielectric relaxation near the curie temperature in triglycine sulfate crystals containing radiation-induced defects and alpha-alanine impurity

The dielectric properties of a polydomain triglycine sulfate (TGS) crystal near the Curie temperature (20 Hz to 20 kHz) were compared with those of mo nodomain crystals (containing alpha -alanine impurity or gamma-irradiated). The frequency and temperature dependences of ac conductivity were used to assess its effect on the dielectric properties of TGS near T-C. The crystal s were found to differ in the variation of the real part of permittivity wi th temperature, which was tentatively attributed to the difference in the d ensity of domain walls in the paraelectric phase near T-C.