Valence Instabilities and Related Narrow-Band Phenomena

Valence Instabilities and Related Narrow-Band Phenomena PDF Author: R. Parks
Publisher: Springer Science & Business Media
ISBN: 1461588162
Category : Science
Languages : en
Pages : 536

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Book Description
Those well-intending workers, especially theorists, who have viewed hungrily the mixed valence problem, but have not yet made the bold leap, might be comforted to learn that the Rochester conference left the virginal state of that problem essentially intact. That is not to say that the event was prosaic. Indeed, the conferees exhibited a level of effervescence appropriate to the freshness and challenge of the problem at hand. If the meeting failed to solve major questions, it at least established several guidelines. One is that future experimental efforts, at least on a short time scale, might be spent most profitably on those substances which exhibit consistent, and hence probably intrinsic, behavior from laboratory to laboratory. A recurring message, not always subtle, to the·theorists was that piecemeal approaches to the mixed valence problem, characteristic of much of the work to date, are of limited usefulness. For at the core of the problem one has a melange of boot-strapping interac tions which must be sorted out and dealt with properly. Para phrasing Phil Anderson (see Epilogue), the mixed valence problem is in the same category of problems which are failing to be done in field theory these days.

Valence Instabilities and Related Narrow-Band Phenomena

Valence Instabilities and Related Narrow-Band Phenomena PDF Author: R. Parks
Publisher: Springer Science & Business Media
ISBN: 1461588162
Category : Science
Languages : en
Pages : 536

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Book Description
Those well-intending workers, especially theorists, who have viewed hungrily the mixed valence problem, but have not yet made the bold leap, might be comforted to learn that the Rochester conference left the virginal state of that problem essentially intact. That is not to say that the event was prosaic. Indeed, the conferees exhibited a level of effervescence appropriate to the freshness and challenge of the problem at hand. If the meeting failed to solve major questions, it at least established several guidelines. One is that future experimental efforts, at least on a short time scale, might be spent most profitably on those substances which exhibit consistent, and hence probably intrinsic, behavior from laboratory to laboratory. A recurring message, not always subtle, to the·theorists was that piecemeal approaches to the mixed valence problem, characteristic of much of the work to date, are of limited usefulness. For at the core of the problem one has a melange of boot-strapping interac tions which must be sorted out and dealt with properly. Para phrasing Phil Anderson (see Epilogue), the mixed valence problem is in the same category of problems which are failing to be done in field theory these days.

Valence Instabilities and Related Narrow- Band Phenomena

Valence Instabilities and Related Narrow- Band Phenomena PDF Author: Ronald D. Parks
Publisher:
ISBN:
Category :
Languages : en
Pages : 0

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Book Description


Narrow-Band Phenomena—Influence of Electrons with Both Band and Localized Character

Narrow-Band Phenomena—Influence of Electrons with Both Band and Localized Character PDF Author: J.C. Fuggle
Publisher: Springer Science & Business Media
ISBN: 1468455591
Category : Science
Languages : en
Pages : 212

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Book Description
The understanding of electronic behaviour in solids when (some of) the valence electrons have both localized and band-like characteristics is one of the central problems of physics and chemistry in the second half of this century. Many advances have indeed been made using highly sophisticated techniques and concepts. Our objectives in bringing together specialists from different areas was cross-fertilization of ideas and redefinition of bottlenecks and problems. The testimony of the participants and the book which follows indicate a fair degree of success. This book is a record of discussions aimed at digestion and reassessment of some of the recent major advances in our understanding of narrow bands. Note that we expressly asked participants to give a short readable account of the major problems in their field and not to emphasize their latest results to be as "technical" as they might be in a normal scientific article. We did not ask for complete reviews of what was going on in the field and this book should not be read as such. Neither should it be approached as the sort of educational text which the NATO ASI proceedings are supposed to be. We have tried to produce a useable account of a workshop in which an attempt was made to define real problems and to distinguish them from illusory problems.

Theoretical and Experimental Aspects of Valence Fluctuations and Heavy Fermions

Theoretical and Experimental Aspects of Valence Fluctuations and Heavy Fermions PDF Author: L.C. Gupta
Publisher: Springer Science & Business Media
ISBN: 1461309476
Category : Science
Languages : en
Pages : 749

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Book Description
During the Koln meeting (August 28-31, 1984), Irdia was chosen as the venue for the next International Conference on Valence Fluctuations. lhis was in recognition ard appreciation of the work done, both experimental ard theoretical, by the Irdian scientists in this area during the last decade. We decided to hold this Conference in the month of January, 1987 at Bangalore. lhe subject of Valence Fluctuations has kept itself alive ard active as it has provided many shocks ard suprises particularly among the Ce- ard U-based intermetallies. lhe richness of many interesting physical phenomena occurring in mixed valent materials, the flexibility of modifying their physical properties (by alloying, for example) ard the possibility of synthesizing a wide variety of new such materials seem to be the key factors in this regard. Barely six months before this Conference, an International Conference on Anomalous Rare Earths and Actinides (ICAREA) had been held at Grenoble (July, 1986) which also focussed on mixed valence ard heavy fermion phenomena. In spite of this, the response to this' Conference was very enthusiastic and encouraging. Many interesting ard important results were presented at this Conference which have been included in this volume.

ERDA Energy Research Abstracts

ERDA Energy Research Abstracts PDF Author: United States. Energy Research and Development Administration
Publisher:
ISBN:
Category : Power resources
Languages : en
Pages : 806

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Book Description


Superconductivity in Ternary Compounds I

Superconductivity in Ternary Compounds I PDF Author: O. Fischer
Publisher: Springer Science & Business Media
ISBN: 3642818684
Category : Technology & Engineering
Languages : en
Pages : 295

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Book Description
The structural. electronic and lattice properties of superconducting ternary com pounds are the subject of this Topics volume. Its companion volume (Topics in Cur rent Physics. Volume 34) deals primarily with the mutual interaction of supercon ductivity and magnetism in ternary compounds. These two volumes are the culmination of a project. started nearly two years ago. that was inspired by the intense re search effort. both experimental and theoretical. then being expended to explore and develop an understanding of the remarkable physical properties of ternary super conductors. Research activity on this subject has increased in the meantime. The interest in ternary superconductors originated in 1972. when B.T. Matthias and his co-workers first discovered superconductivity in several ternary molybdenum sulfide compounds that had been synthesized in 1971 by R. Chevrel. M. Sergent. and J. Prigent. The superconducting critical temperature Tc of one of the compounds. PbMo S • was reported to be ~ 15 K. This value is sufficiently high that there was g 6 (and still is) reason to expect that other ternary compounds would be found with superconducting transition temperatures rivaling those of the A15 compounds. of which Nb Ge has the record high Tc of 23 K. The interest in ternary superconductors 3 received further impetus when several of the ternary molybdenum sulfides were found to have exceptionally high upper critical magnetic fields. some of them in the neighborhood of 50 Tesla or more. An immense amount of research on ternary molybdenum chalcogenides then followed.

Properties and Applications of Thermoelectric Materials

Properties and Applications of Thermoelectric Materials PDF Author: Veljko Zlatic
Publisher: Springer Science & Business Media
ISBN: 9048128927
Category : Technology & Engineering
Languages : en
Pages : 340

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Book Description
As concerns with the efficient use of energy resources, and the minimization of environmental damage have come to the fore, there has been a renewed interest in the role that thermoelectric devices could play in generating electricity from waste heat, enabling cooling via refrigerators with no moving parts, and many other more specialized applications. The main problem in realizing this ambition is the rather low efficiency of such devices for general applications. This book deals with the proceedings of a workshop addressed that problems by reviewing the latest experimental and theoretical work on suitable materials for device applications and by exploring various strategies that might increase their efficiency. The proceedings cover a broad range of approaches, from the experimental work of fabricating new compounds through to theoretical work in characterizing and understanding their properties. The effects of strong electron correlation, disorder, the proximity to metal-insulator transitions, the properties of layered composite materials, and the introduction of voids or cages into the structure to reduce the lattice thermal conductivity are all explored as ways of enhancing the efficiency of their use in thermoelectric devices.

Electron Correlation and Magnetism in Narrow-Band Systems

Electron Correlation and Magnetism in Narrow-Band Systems PDF Author: T. Moriya
Publisher: Springer Science & Business Media
ISBN: 3642816398
Category : Science
Languages : en
Pages : 270

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Book Description
Speech by Toyosaburo Taniguchi Welcome my friends to the Third International Symposium, Division on the Theory of Condensed Matter, of the Taniguchi Foundation. The need is now greater than ever for Japan to consider how to strengthen and foster international understanding between nations, peoples and societies, and how to contribute towards the establishment of peace and prosperity in the world. For more than twenty years, I have been supporting a symposium on mathe matics in which distinguished scholars from allover the world have engaged in free discussions. In this symposium, all the participants live together in community style. I have heard from members of some of these study groups that this type of setup has helped to strengthen their ties and relationships with their colleagues on a personal basis. What developed in the mathematics group led me to reorganize and strengthen the Taniguchi Foundation only a few years ago through additional funding. In order to effectively translate the objectives of the Foundation into action with the funds available, it becomes necessary to select those fields which are not necessarily in the limelight of popular interest, which means those fields which, I am afraid, are low in funding. I would rather choose from modest unimpressive academic fields than for the Foundation, projects those that stand out in gaudy, gorgeous popular acclaim.

Proceedings of the International Symposium on Topological Aspects of Critical Systems and Networks, Sapporo, Japan, 13-14 February 2006

Proceedings of the International Symposium on Topological Aspects of Critical Systems and Networks, Sapporo, Japan, 13-14 February 2006 PDF Author: Kousuke Yakubo
Publisher: World Scientific
ISBN: 9812708685
Category : Electric network topology
Languages : en
Pages : 280

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Book Description
This volume gives an interdisciplinary discussion on the topological aspects of general networks and critical systems for physicists, chemists, biologists, mathematicians, medical scientists, social scientists, and other related researchers. Subjects as diverse as the general properties of complex networks, complexity in social science, patterns in biological objects, and criticality in pure and applied physics are represented. The book is essential for researchers in a wide range of scientific and technological fields related to these areas.

Science and Technology of Rare Earth Materials

Science and Technology of Rare Earth Materials PDF Author: E C Subbarao
Publisher: Elsevier
ISBN: 0323138977
Category : Science
Languages : en
Pages : 454

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Book Description
Science and Technology of Rare Earth Materials reviews the important aspects of the science and technology of rare earth materials, covering the entire spectrum from occurrence to extraction and purification, phase relationships, electronic structure, and applications. This book is organized into five sections encompassing 19 chapters. The occurrence, extraction, and production of rare earths are discussed in the first section, followed by purification methods employed for rare earths, together with the role of impurities on their behavior. The phase relations among the rare earth alloys, including a particular reference to the technologically important rare earth-cobalt alloys, and phase relations among the rare earth oxides are considered in the second section. The succeeding two sections focus on studies of the electronic structure of rare earth materials, with emphasis on the use of nuclear magnetic resonance and Mössbauer spectroscopy. Theoretical conceptions are set forth as well as the effect of crystal fields and valence fluctuations on the properties of rare earth systems. The final section describes some of the extensive current uses of rare earth materials such as in the steel industry and in permanent magnets, as well as emerging applications in catalysis, hydrogen storage, ferroelectrics, and fast ion conductors. This book is a valuable resource for researchers and students interested in rare earths.