Cryst. Res. Technol. 38, No. 6, 465 – 470 (2003) / DOI 10.1002/crat.200310058 2003 © 2003 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim 0232-1300/03/0606-0465 $ 17.50+.50/0 Electrical and dielectric behavior of the system Gd 1-x Ba x CoO 3 (x = 0.00, 0.10, 0.20) synthesized by chemical route K. D. Mandal* 1 , L. Behera 1 , R. L. Prasad 1 , and R. C. Behera 2 1 Department of Chemistry, North Eastern Regional Institute of Science & Technology, Nirjuli, Itanagar – 791109, Arunachal Pradesh, India 2 Department of Metallurgical Engineering, Regional Engineering College,Rourkela-769008, Orissa, India Received 7 June 2002, revised 27 August 2002, accepted 17 February 2003 Published online 15 June 2003 Key words gadolinium cobalt oxide, perovskite oxides, chemical synthesis, electrical transport, dielectric response. PACS 72.20.-i The samples in the system Gd 1-x Ba x CoO 3 (x = 0.00, 0.10, 0.20) were prepared by chemical route. These samples form single-phase materials, which were confirmed by XRD and TGA studies. The presence of interfacial polarization is responsible for high value of dielectric constant in these materials. The conductivity observed in Gd 1-x Ba x CoO 3 system may be due to mobile holes created by excitation of an electron from the π* band to an acceptor level. 1 Introduction The perovskite oxide is a field of great interest for Material Scientests. A number of perovskite oxides have been studied by various groups of workers [1,2,3]. Perovskite oxides have been studied extensively because of their technological applications. The reason for broad application includes their stability over wide temperature ranges and their low cost and ease with which composition and microstructure may be optimized and tailored to specific applications [4,5,6]. Rare earth cobaltates show interesting electrical and magnetic properties. The properties of those materials depends on spin state and valance state of transition metal ions and ionic radii of rare earth ions [7]. We have been studying electrical and dielectric properties of perovskite oxides and valance compensated perovskite oxides [8,9,10,11] which were synthesized by conventional ceramic method. Recently we have taken up few systems of perovskite oxides, which were synthesized by chemical route and published elsewhere [10,12]. In this paper we report the method of synthesis of the Gd 1-x Ba x CoO 3 (x = 0.00, 0.10, 0.20) system by the chemical route and study the electrical and dielectric properties. The change in electrical and dielectric properties in the system with doping of Ba +2 ions is also explained. 2 Experiment Compositions with x=0.00, 0.10, 0.20, in the system Gd 1-x Ba x CoO 3 were prepared by chemical method using Citric acid. All chemicals used in this method has purity 99.9% or betters. Gadolinium Oxide, Cobalt (II) nitrate and Barium nitrate were used as starting materials. Gadolinium oxide was converted into nitrate by adding conc.HNO 3 and evaporated to dryness. Standard solution of metal nitrate was prepared in distilled water. Solution having stoichiometric amount of those ____________________ * Corresponding author: e-mail: kdm@nerist.ernet.in