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[...]... Introduction and Crystal Chemistryof Oxide Superconductors Bertrand L Chamberland 1 O INTRODUCTION The objectives of this chapter are to introduce the reader to the interesting and important phenomenon of superconductivity in various materials We begin with the original discovery of superconductivity and proceed to the investigation of the chemical elements, then metallic alloys, and finally to ceramic and. .. reading of each manuscript The tireless efforts of George Narita were responsible for both the genesis and realization of this project, and I will always cherish the unwavering support and encouragement given to me by Charlotte Lowe-Ma and David Vanderah China Lake, California October 9, 1990 Terrell A Vanderah Contents PART I INTRODUCTION 1 HISTORICAL INTRODUCTION AND CRYSTAL CHEMISTRYOF OXIDE SUPERCONDUCTORS... structural and chemical characterization, and chemistry- structureproperty relations of these fascinating materials This book has in large part been written by members of that subspecies of inorganic chemistry called solid state chemistry, a specialization that evolved during the heyday of the semiconductor device, and which now seems uniquely suited for the challenging chemistryof high-T, compounds Hence,... Structures of the Perovskite-Related YBa,Cu,O, 488 YBa#u40s, and Y.$a.,Cu701s Superconductors 488 2.1 123 Superconductor 490 2.2 124 and 247 Superconductors 3 Structures of the Perovskite/Rock Salt 490 Superconductors 490 3.1 Lanthanum-Containing Superconductors 491 3.2 Bismuth-Containing Superconductors 493 3.3 Thallium-Containing Superconductors 495 3.4 Thallium-Lead Containing Superconductors... descriptions of physical properties and experimental results presented in several of the Physics journals The theoretical aspects of superconductivity will also be omitted, as well as the practical application and engineering aspects of these new materials 4 ChemistryofSuperconductor Materials 1 l Discovery of Superconductivity At very low temperatures, the movement of atoms, ions, and molecules... reported by Hulm and 12 Chemistryof Superconductor Materials Figure 3: The increase in superconducting transition temperature (T, / K) as a function of year, from the discovery of superconductivity in 1911to 1973 Figure 4: A plot of critical temperature (TJK) W~SUS number the of valence electrons per atom in the intermetallic A-15 materials Historical Introduction and Crystal Chemistryof Oxide Superconductors... structures, and tables of X-ray diffraction data) as well as a review of the literature into 1990 The introductory chapter describes the detailed chemical history of superconductivity, beginning with the first observation of the phenomenon in the element Hg in 1911 Thereafter, the chapters are partitioned into three sections emphasizing synthesis and crystal chemistry, sample characterization, and chemistry- structure-property... supercurrent Plow and Esaki Kunzler B Josephson, et al through a tunnel barrier ‘964 Rediction 1973-Q Critical 9 of high-Tc temperature in Nb3G?, surpassing ‘986 Evidence of high-Tc ‘987 Observation in organic compds of 23 K is reached the liq H2 barrier in La-Ba-Cu-oxides of 95 K T, in Y-E!a-Cu-0 W A Little J Gavaler/Westinghouse, and also Bell Labs MDller and Bednorz Chu and Wu 10 Chemistry of Superconductor. .. units), and its critical current (given in units of Amperes) Our presentation is aimed principally on the single property of critical transition temperature (T,), since it is controlled 2 Historical Introduction and Crystal Chemistry of Oxide Superconductors 3 primarily by the chemical composition and the structural arrangement of atoms These two factors are of primary concern to the chemist and material... to certify that a material is superconducting These are: long-term stability, and reproducibility in the preparation and physical property determination Historical Introduction and Crystal Chemistryof Oxide Superconductors 7 8 Chemistry TABLE 1: Element Tc ofSuperconductor Materials Superconducting Transition Elements and Alloys T, (K) 11.2 Temperatures Alloy Nb3ce for Selected Tc (K) 23.2 Nb 9.46 . 10987654321 Library of Congress Cataloging-in-Publication Data Chemistry of superconductor materials : preparation, chemistry, characterization and theory / edited by Term11 A. Vanderah. p. cm reference text for those interested in the preparation, crystal chemistry, structural and chemical characterization, and chemistry- structure- property relations of these fascinating materials. This. synthesis and crystal chemistry, sample characterization, and chemistry- structure-property relations. The section on Structural and Preparative Chemistry contains ten chapters, three of which, using