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Valence bond theory
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ISBN: 9780444508898 0444508899 9780080543499 0080543499 1281048534 9786611048532 Year: 2002 Publisher: Amsterdam ; Boston : Elsevier,

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Valence bond (VB) theory, which builds the descriptions of molecules from those of its constituent parts, provided the first successful quantum mechanical treatments of chemical bonding. Its language and concepts permeate much of chemistry, at all levels. Various modern formulations of VB theory represent serious tools for quantum chemical studies of molecular electronic structure and reactivity. In physics, there is much VB-based work (particularly in semi-empirical form) on larger systems. Importance of TopicThe last decade has seen significant advances in methodology and a vast incr


Book
Valency and molecular structure
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ISBN: 0408690003 Year: 1970 Publisher: London Butterworths

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Coordinative interactions
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ISBN: 3540064109 0387064109 3540377395 Year: 1973 Publisher: Berlin : Springer-Verlag,

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Valency and bonding
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ISBN: 0521831288 9780521831284 9780511614569 9780521538527 Year: 2005 Publisher: Cambridge Cambridge University Press

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Book
Electronic Structure of Semiconductor Interfaces
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ISBN: 9783031590641 Year: 2024 Publisher: Cham Springer Nature Switzerland :Imprint: Springer

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This concise volume examines the characteristic electronic parameters of semiconductor interfaces, namely the barrier heights of metal–semiconductor or Schottky contacts and the valence-band discontinuities of semiconductor–semiconductor interfaces or heterostructures. Both are determined by the same concept, namely the wave-function tails of electron states overlapping a semiconductor band gap directly at the interface. These interface-induced gap states (IFIGS) result from the complex band structure of the corresponding semiconductor. The IFIGS are characterized by two parameters, namely by their branch point, at which their charge character changes from predominantly valence-band- to conduction-band-like, and secondly by the proportionality factor or slope parameter of the corresponding electric-dipole term, which varies in proportion to the difference in the electronegativities of the two solids forming the interface. This IFIGS-and-electronegativity concept consistently and quantitatively explains the experimentally observed barrier heights of Schottky contacts as well as the valence-band offsets of heterostructures. Insulators are treated as wide band-gap semiconductors. In addition, this book: Explains the formation of interface-induced gap states and electric dipoles in Schottky contacts and heterostructures Includes experimental Schottky barrier heights, slope parameters, and valence-band offsets for a range of semiconductors Compares theoretical and experimental barrier heights of Schottky contacts and valence-band offsets of heterostructures.

Pauling's legacy : modern modelling of the chemical bond
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ISBN: 0444825088 9780444825087 9780080538525 0080538525 9786611119997 1281119997 Year: 1999 Publisher: Amsterdam ; New York : Elsevier,

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Theory and experiment in chemistry today provide a wealth of data, but such data have no meaning unless they are correctly interpreted by sound and transparent physical models. Linus Pauling was a grandmaster in the modelling of molecular properties. Indeed, many of his models have served chemistry for decades and that has been his lasting legacy for chemists all over the world. The aim of this book is to put such simple models into the language of modern quantum chemistry, thus providing a deeper justification for many of Pauling's ideas and concepts. However, it should be stressed that ma

Valence bond methods
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ISBN: 9780511535383 9780521803922 9780521021272 0511020376 9780511020377 0511535384 1280433361 9781280433368 051115805X 9780511158056 0511043872 9780511043871 0521803926 1107123542 9781107123540 0511177135 9780511177132 0511304846 9780511304842 0521021278 9786610433360 6610433364 Year: 2002 Publisher: Cambridge New York Cambridge University Press

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Valence bond theory is one of two commonly used methods in molecular quantum mechanics, the other is molecular orbital theory. This book focuses on the first of these methods, ab initio valence bond theory. The book is split into two parts. Part I gives simple examples of two-electron calculations and the necessary theory to extend these to larger systems. Part II gives a set of case studies of related molecule sets designed to show the nature of the valence bond description of molecular structure. It also highlights the stability of this description to varying basis sets. There are references to the CRUNCH computer program for molecular structure calculations which is currently available in the public domain. The book will be of primary interest to researchers and students working on electronic theory and computation in chemistry and chemical physics.


Book
Chapters of dependency grammar
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ISBN: 9789027261700 9027261709 9027204764 9789027204769 Year: 2020 Publisher: Amsterdam Philadelphia

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"Was Tesnière the founding father of dependency grammar or merely a culmination point in its long history? Leaving no doubt that the latter position is correct, Chapters of Dependency Grammar tells the story of how dependency-oriented grammatical description developed from Antiquity up to the early 20th century. From Priscian's Rome to Dmitrievsky's Russia, from the French Encyclopaedia to Stephen W. Clark's school grammars in 19th century America, it is shown how the concept of dependencies (asymmetric word-to-word relations) surfaced again and again, assuming a central place in syntax. A particularly intriguing aspect of the storyline is that even without any direct contact or influence, authors were making key breakthroughs in similar directions. In the works of Sámuel Brassai, a Transylvanian polymath, and Franz Kern, a German grammarian, the first dependency trees appear in 1873 and 1883, respectively, predating Tesnière's stemmas by several decades"--


Book
Ten Studies in Dependency Syntax
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ISBN: 9783110694765 311069476X 3110694700 Year: 2021 Publisher: Berlin Boston

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The monograph presents the Meaning-Text approach applied to the domain of syntax from a typological angle; it deals with several long-standing syntactic problems on the basis of a dependency description.Its content can be presented in five parts + an Introduction:The Introduction explains the architecture of the book and sketches the Meaning-Text linguis-tic model, underlying the subsequent discussion.I. Surface-syntactic relations in the languages of the world, with special studies of subjects and objects.II. Grammatical voice in the dependency framework: the “passive” construction in Chinese.III. The relative clause: a calculus and analysis of possible types; the pseudo-relative (“headless”) clause.IV. Binary conjunctions (such as IF …, THEN …), free indefinite pronouns ([He went] nobody knows where), and syntactic idioms.V. Word order: linearization of dependency structures.The monograph offers a new perspective in syntactic studies. It is strongly typology-oriented (using the data from typologically diverse languages: English, Russian, Chinese, Korean, Basque, Georgian, etc.) and based on a system of rigorous definitions of the notions involved, which ensures a link with computational linguistics and Natural Language Processing

Markierte Valenze im Sprachvergleich: Lizenzierungs- und Linkingbedingungen
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ISBN: 3484304111 3110924811 Year: 2000 Volume: 411 Publisher: Tübingen Max Niemeyer Verlag

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In dieser Arbeit wird im Rahmen der multidimensionalen Valenztheorie und einem Modell thematischer Proto-Rollen eine universelle Theorie des Linkings von Kasus mit thematischen Rollen entwickelt, die nicht nur Voraussagen über unmarkierte Valenzen, z.B. Nominativ-Akkusativ bzw. Absolutiv-Ergativ, sondern auch über markierte, z.B. Nominativ- bzw. Absolutiv-Dativ, macht. Anhand umfangreicher Datensammlungen aus 11 Sprachen wird gezeigt, daß markierte Valenzen sprachübergreifend häufig bei Verben mit bestimmten Bedeutungen auftreten und dabei z.T. gegenüber unmarkierten präferiert sind. In der Literatur wurde bisher nur ein Teilbereich dieses Phänomens berücksichtigt, nämlich Dativ-Experiencer-Verben wie z.B. gefallen, deren Linkingverhalten zumeist durch die Funktion des Dativs, den Experiencer zu kodieren, erklärt wird. Solche Ansätze werden jedoch den Daten nicht gerecht, da die vielfältigen markierten Valenzen bei Psychverben oft keinen Dativ enthalten. Zudem wurde bislang den sprachübergreifend verbreiteten agentiven Verben mit markierten Valenzen, z.B. Interaktionsverben wie helfen und folgen nicht Rechnung getragen (umfangreiche Listen solcher Verben finden sich im Anhang) bzw. die Kasuswahl dieser Verben als idiosynkratisch behandelt. Es wird eine Markiertheitstheorie für Valenzen eingeführt, die die unterschiedliche Frequenz der belegten Valenzen vorhersagt, und es wird nachgewiesen, daß markierte Valenzen nicht durch die Affinität bestimmter Kasus zu bestimmten thematischen Rollen zustandekommen, sondern als Ganzes zur morphosyntaktischen Markierung von Verben dienen, deren Argument- und Situationsstruktur von dem für transitive Verben üblichen Muster abweicht.

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