Structure-Property Relationships in Superconducting Cuprates

Department of Chemistry, University of Wales, Cardiff CF1 3TB, U.K., and Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560 012, India A. K. Ganguli 

CSIR Centre of Excellence in Chemistry, Indian Institute of Science, Bangalore 560 012, India 

Ganguli is a scientific officer at the Centre of Excellence in Chemistry at the Indian Institute of Science. He has an M.Sc. degree from the University of Delhi andaPh.D. degree from the Indian Institute of Science and has carried out post-doctoral work at du Pont and Iowa State University. 

Rao is a Professor of Chemical Science at the Indian Institute of Science, and President of the Jawaharalal Nehru Centre for Advanced Scientific Research, Bangalore, India. He is an Honorary Professor of Chemistry at the University of Wales, Cardiff. He was Commonwealth Visiting Professor at the University of Oxford and Nehru Professor at the University of Cambridge. He is a Fellow of the Royal Society, London, Foreign Associate of the U.S. National Academy of Sciences, and Foreign member of several other academies. He is a member of the Pontifical Academy of Sciences and an Honorary Fellow of the Royal Society of Chemistry. He is a recipient of the Marlow Medal of the Faraday Society and the RSC Medal for solid-state chemistry. His main research interests are in solid-state chemistry, spectroscopy, and molecular structure and surface science. He is the author of over 500 research papers and several books in solid state chemistry. 

Based on the interplanar Cu—Cu distances, one can classify cuprates into two categories.9 In one category, r(Cu—Cu) lies 

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STRUCTURE-PROPERTY RELATIONSHIPS IN SUPERCONDUCTING CUPRATES—C. N. R. RAO AND A. K. GANGULI 3... 

Although the high-temperature superconducting phases are formed from insulating materials by the introduction of defects, the precise relationship between dopant, structure, and properties is not fully understood yet. For example, in most of the cuprate phases it is extremely difficult to be exactly sure of the charges on the individual ions, and because of this the real defect structures are still uncertain. 

Investigations of the relationships between the composition, crystal structure and superconducting properties of different families of layered cuprates resulted in empirical criteria that have to be fulfilled for superconductivity to appear [65] ... 

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