The Experts below are selected from a list of 63 Experts worldwide ranked by ideXlab platform
Alexander V Savin - One of the best experts on this subject based on the ideXlab platform.
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vibrational tamm states at the edges of grapheme nanoribbons
Physical Review B, 2010Co-Authors: Alexander V Savin, Yuri S KivsharAbstract:We study vibrational states localized at the edges of graphene nanoribbons. Such surface oscillations can be considered as a phonon analog of Tamm states in the Electronic Theory. We consider both armchair and zigzag graphene stripes and demonstrate that surface modes correspond to phonons localized at the edges of the graphene nanoribbon, and they can be classified as in-plane and out-of-plane modes. In armchair nanoribbons anharmonic edge modes can experience longitudinal localization in the form of self-localized nonlinear modes or surface breather solitons.
Kevin S Bedell - One of the best experts on this subject based on the ideXlab platform.
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the Theory of superconductivity in the high tc cuprates
Physics Today, 1998Co-Authors: P W Anderson, Kevin S BedellAbstract:This book is P. W. Anderson's long-awaited full presentation of his Theory of high-T"c" superconductivity in the cuprates. He realized that this striking new phenomenon needed for its explanation not just a new mechanism or "gimmick" but a radical reworking of the Electronic Theory of metals, especially those of low dimension. The many fundamentally new ideas that are first fully presented here will require a rewriting of the textbooks of many-body Theory, which may take decades. The book incorporates full discussions of the experimental situation in these complex materials, both the normal and the superconducting states. The latest advances are contained in a selection of re-and pre-prints of recent work by Anderson and collaborators. The fundamental insight contained in the book is that the conditions for validity of the renormalized quasiparticle Theory of metals ("Fermi Liquid Theory") are much more restrictive than had been thought, and are not satisfied in the CuO"2" planes of high-T"c" materials (among, probably, many other examples). This requires a new state of matter to be invented, new transport theories, and new mechanisms for superconductivity. This book will supersede all theoretical discussions of superconductivity that are now available in book form. Originally published in 1997. The Princeton Legacy Library uses the latest print-on-demand technology to again make available previously out-of-print books from the distinguished backlist of Princeton University Press. These editions preserve the original texts of these important books while presenting them in durable paperback and hardcover editions. The goal of the Princeton Legacy Library is to vastly increase access to the rich scholarly heritage found in the thousands of books published by Princeton University Press since its founding in 1905.
J Haber - One of the best experts on this subject based on the ideXlab platform.
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fifty years of my romance with vanadium oxide catalysts
Catalysis Today, 2009Co-Authors: J HaberAbstract:Abstract The fifties of XXth century were times when solid state physics and chemistry scored great successes both experimental and theoretical – transistors were discovered and the Theory of Electronic structure of solids made rapid progress. It was believed that this Theory will permit the understanding of the mechanism of chemical reactions at metal and oxide surfaces and Electronic Theory of catalysis was developed. Vanadium oxides were a good example to be studied, because extremely rich chemistry of vanadium oxides and vanadium oxide based catalysts results from a number of different interrelated Electronic and structural factors. These compounds have partially filled d-orbitals which are responsible for a wide variety of Electronic, magnetic and catalytic properties. The phase diagram shows that vanadium atoms exist in different formal oxidation states, which vary from two to five. The easy conversion between oxides of different stoichiometry and formation of oxygen vacancies enables the oxide to function as catalyst in selective oxidation. Exposed to gas phase of sufficient redox potential reduction and reconstruction of the surface into V 6 O 13 phase may take place. Due to the anisotropy of crystallites different crystal planes have different adsorption properties and different catalytic active sites are present. Reducibility depends on the degree of dispersion. When deposited on other oxide supports their wetting is observed and surface migration from one support onto another one may take place depending on the surface free energy ratio. On exposure to water vapour, the vanadium monolayer transforms into polyanions. Depending on the type of support vanadium oxide shows various catalytic properties. The quantum-chemical calculations show that nonbonding d-orbitals of vanadium ions have the LUMO character and act as Lewis acid sites, whereas the lone electron pairs of bridging oxygen ions have the HOMO character and behave as Lewis basic sites. Cleavage along (1 0 0) planes leaves coordinatively unsaturated vanadium and oxygen ions which develop Bronsted acid–base interactions with reacting molecules and cause their heterolytic chemisorption. On the basis of the results collected in the last 50 years a book on physical chemistry of vanadium–oxygen system could be written.
Yuri S Kivshar - One of the best experts on this subject based on the ideXlab platform.
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vibrational tamm states at the edges of grapheme nanoribbons
Physical Review B, 2010Co-Authors: Alexander V Savin, Yuri S KivsharAbstract:We study vibrational states localized at the edges of graphene nanoribbons. Such surface oscillations can be considered as a phonon analog of Tamm states in the Electronic Theory. We consider both armchair and zigzag graphene stripes and demonstrate that surface modes correspond to phonons localized at the edges of the graphene nanoribbon, and they can be classified as in-plane and out-of-plane modes. In armchair nanoribbons anharmonic edge modes can experience longitudinal localization in the form of self-localized nonlinear modes or surface breather solitons.
P W Anderson - One of the best experts on this subject based on the ideXlab platform.
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the Theory of superconductivity in the high tc cuprates
Physics Today, 1998Co-Authors: P W Anderson, Kevin S BedellAbstract:This book is P. W. Anderson's long-awaited full presentation of his Theory of high-T"c" superconductivity in the cuprates. He realized that this striking new phenomenon needed for its explanation not just a new mechanism or "gimmick" but a radical reworking of the Electronic Theory of metals, especially those of low dimension. The many fundamentally new ideas that are first fully presented here will require a rewriting of the textbooks of many-body Theory, which may take decades. The book incorporates full discussions of the experimental situation in these complex materials, both the normal and the superconducting states. The latest advances are contained in a selection of re-and pre-prints of recent work by Anderson and collaborators. The fundamental insight contained in the book is that the conditions for validity of the renormalized quasiparticle Theory of metals ("Fermi Liquid Theory") are much more restrictive than had been thought, and are not satisfied in the CuO"2" planes of high-T"c" materials (among, probably, many other examples). This requires a new state of matter to be invented, new transport theories, and new mechanisms for superconductivity. This book will supersede all theoretical discussions of superconductivity that are now available in book form. Originally published in 1997. The Princeton Legacy Library uses the latest print-on-demand technology to again make available previously out-of-print books from the distinguished backlist of Princeton University Press. These editions preserve the original texts of these important books while presenting them in durable paperback and hardcover editions. The goal of the Princeton Legacy Library is to vastly increase access to the rich scholarly heritage found in the thousands of books published by Princeton University Press since its founding in 1905.