Department of Physics, T.D. Post Graduate College Jaun-UP India

Email:-ant_tdc@yahoo.com

A heavy rare-earth zirconate R₂Zr₂O₇ compound (where R = Y & Gd) was prepared by solid state reaction at 1300K for 50h. The prepared compound has been characterized by X-ray diffraction (XRD), differential thermal analysis (DTA), thermogravimetric analysis (TGA) and derivative thermogravimetry (DTG). The XRD Studies indicates the formation of single phase orthorhombic structure at room temperature. The electrical conductivity of R₂Zr₂O₇compound were measured in the temperature range 300-1125 K at an internal frequency of 1 kHz. The logs vs. 10³/T plot yield the different slopes separated by break temperature (T₁). The activation energy below and above this break temperature have been estimated as approximately 0.10eV and 3eV respectively. Hence the electrical conduction below T₁ is essentially extrinsic always associated with impurities, defects and interstitials and conduction above T₁ is essentially intrinsic due to the change in conduction mechanism.