New Phase Transitions in Perovskite Oxides: BiFeO3, SrSnO3, and Pb(Fe2/3W1/3)1/2Ti1/2O3

• Published in: Journal of the American Ceramic Society Vol. 91; no. 6; pp. 1762 - 1768
• Main Authors: Scott, James F., Palai, Ratnakar, Kumar, Ashok, Singh, Manoj K., Murari, Nishit M., Karan, Naba K., Katiyar, Ram S.
• Format: Journal Article
• Language: English
• Published: Malden, USA Blackwell Publishing Inc 01-06-2008; Blackwell
• Subjects: Applied sciences; Building materials. Ceramics. Glasses; Ceramic industries; Chemical industry and chemicals; Condensed matter: structure, mechanical and thermal properties; Crystalline state (including molecular motions in solids); Crystallographic aspects of phase transformations; pressure effects; Electrotechnical and electronic ceramics; Exact sciences and technology; Physics; Structure of solids and liquids; crystallography; Technical ceramics; Perovskite type compound; Film; Bismuth Iron Oxides Mixed; Oxides; Titanates; Differential thermal analysis; High temperature; Experimental study; Tin Strontium Oxides Mixed; Oxide ceramics; Ferrites; Ferroelectric transition; Phase transformation; Metal insulator transition; Raman spectrum; Electroceramics; Iron Lead Tungsten Titanates Mixed; Crystalline structure
• ISSN: 0002-7820; 1551-2916
• DOI: 10.1111/j.1551-2916.2008.02404.x

This paper reports on two new aspects of oxide perovskites: the first part is devoted to new phase transitions, especially at high temperatures; multiferroics such as BiFeO3 and Pb–Fe–W–titanate are emphasized but nonmagnetic materials such as SrSnO3 are included. The work summarized on bismuth ferrite emphasizes its metal–insulator transition near 1200 K (atmospheric pressure) and 47 GPa (room temperature); that on SrSnO3 emphasizes order–disorder phase transitions; and that on lead–iron tungstate–titanate exhibits a classic second‐order ferroelectric phase transition, of which rather few are known in the literature. The second part of the paper presents a discussion of constant phase elements for oxide perovskite ceramics; this is a modern way of characterizing their dielectric relaxation, particularly near phase transition temperatures.