Theory of Chemisorption

Theory of Chemisorption

Author: J. R. Smith

Publisher: Springer Science & Business Media

Published: 2013-03-08

Total Pages: 247

ISBN-13: 364281431X

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The theory of the chemical interaction of molecules with surfaces has advanced handsomely in the last few years. This is due in part to the application of the entire arsenal of bulk solid-state theory and molecular quantum chemistry methods. This considerable activity was stimulated by an outpouring of experimental data, particularly of photoemission spectra. In many cases the theoretical techniques are now such that accurate, atomistic pictures of chemisorption phenomena are computed from first principles. This level of capability has been reached only recently, and has not been described anywhere in a comprehensive manner. The purpose of this monograph is to review these recent advances and, at the same time, to indicate a number of important questions which have not been answered. We discuss chemisorption on oxides, semiconductors, and both simple and transition metals. Solid surfaces as well as clusters are considered. While the review should be valuable to workers in the field, care has been taken to make the chapters understandable to the nonspecialist.


Quantum Chemistry Approaches to Chemisorption and Heterogeneous Catalysis

Quantum Chemistry Approaches to Chemisorption and Heterogeneous Catalysis

Author: F. Ruette

Publisher: Springer Science & Business Media

Published: 2013-03-14

Total Pages: 379

ISBN-13: 9401728259

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The development of "high-tech" materials in contemporary industries is deeply related to a detailed understanding of specific surface properties of catalysts which make particular reactions possible. But this understanding presupposes that there exists a body of theory capable of explaining situations not easily accessible to experimental methods and of relating experimental findings among themselves and with theoretical constructs. For these reasons, theoretical developments in surface physics and surface chemistry of transition metal compounds have been of paramount importance in promoting progress in catalysis, electronic devices, corrosion, etc. Although a great variety of spectroscopic methods for analyzing solids and surfaces at molecular scale have been introduced in recent years, nevertheless, many questions about the adsorption sites and intermediates, the effect of promoters, the poisoning of active sites, the nature of segregation of impurities, the process of surface reconstruction, the mechanisms of reactions, etc. have remained unanswered simply because of the great complexity of surface phenomena. It is in this sense that quantum mechanical method- combined with experimental data - may shed some light on the microscopic properties of new surface materials.


Chemisorption and Magnetization

Chemisorption and Magnetization

Author: P. W. Selwood

Publisher: Elsevier

Published: 2012-12-02

Total Pages: 185

ISBN-13: 0323160565

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Chemisorption and Magnetization focuses on particle size determination and on the number of adsorbent atoms affected when any molecule is adsorbed on a surface. This book examines the adsorption of a molecule on the surface of a ferromagnetic solid that produces a change in the magnetization of the solid. Organized into 12 chapters, this book starts with an overview of the experimental methods used for studying chemisorption and magnetization, which are applicable in granulometry. This text then discusses the measurement of saturation magnetization in a ferromagnetic substance in the form of small particles. Other chapters consider the conditions in a typical nickelâ€"silica hydrogenation catalyst. This text examines as well the magnetization at moderate fields and near room temperature. The final chapter deals with the properties and complexities of palladium, platinum, and nickel. Students and researchers interested in heterogeneous catalysis and related areas will find this book extremely useful.


Electronic Processes on Semiconductor Surfaces during Chemisorption

Electronic Processes on Semiconductor Surfaces during Chemisorption

Author: T. Wolkenstein

Publisher: Springer Science & Business Media

Published: 2012-12-06

Total Pages: 457

ISBN-13: 1461536561

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"Hands are useless if there are no eyes to see what is obvious." -M. V. Lomonosov Dear Reader, I invite you to open this book and step on the semiconductor surface, where the processes that form the subject of the book come into play. The surface of the semiconductor is attracting more and more interest among researchers, in fact researchers in two different fields. These are notably the physicists and engineers engaged in research in semi conductor physics and the making of semiconductor devices. The entire industry of semiconductor instruments hinges on the problem of the surface. The quality of semiconductor devices, whose use is growing steadily, depends essentially on the properties of the surface. The instability of these properties and their uncon trollable alterations with temperature and under the influence of environmental conditions result in a lack of stability in the performance of semiconductor devices, hence the high percentage of waste in their industrial production. The methods used in factory laboratories to prevent such waste are largely empirical. The properties of the surface, the nature of the physicochemical processes that take place on it, and the role of environmental factors still remain obscure. A major task of the semiconductor industry is to learn to control the properties of the surface.


Chemisorption and Reactivity on Supported Clusters and Thin Films:

Chemisorption and Reactivity on Supported Clusters and Thin Films:

Author: R.M. Lambert

Publisher: Springer Science & Business Media

Published: 2013-04-17

Total Pages: 534

ISBN-13: 9401589119

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Heterogeneous catalysis provides the backbone of the world's chemical and oil industries. The innate complexity of practical catalytic systems suggests that useful progress should be achievable by investigating key aspects of catalysis by experimental studies on idealised model systems. Thin films and supported clusters are two promising types of model system that can be used for this purpose, since they mimic important aspects of the properties of practical dispersed catalysts. Similarly, appropriate theoretical studies of chemisorption and surface reaction clusters or extended slab systems can provide valuable information on the factors that underlie bonding and catalytic activity. This volume describes such experimental and theoretical approaches to the surface chemistry and catalytic behaviour of metals, metal oxides and metal/metal oxide systems. An introduction to the principles and main themes of heterogeneous catalysis is followed by detailed accounts of the application of modern experimental and theoretical techniques to fundamental problems. The application of advanced experimental methods is complemented by a full description of theoretical procedures, including Hartree-Fock, density functional and similar techniques. The relative merits of the various approaches are considered and directions for future progress are indicated.


Chemisorption And Reactions On Metallic Films V2

Chemisorption And Reactions On Metallic Films V2

Author: J Anderson

Publisher: Elsevier

Published: 2012-12-02

Total Pages: 336

ISBN-13: 0323155316

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Chemisorption and Reactions on Metallic Films, Volume 2 is a four-chapter text that describes the role of evaporated metal films in advancing the understanding of the metal-gas interface chemistry and in understanding of adsorption and catalysis at metal surfaces. This volume first describes film structure and properties, particularly of random polycrystalline films, as well as the concepts of the adsorption and kinetic phenomena. The topic is followed by an overview of the main classes of catalytic reactions that have been studied over evaporated metal film catalysts. A chapter explores the preparation, characterization, structure, and surface properties of alloy films. The theory of the oxidation of metals and the advantages and disadvantages of using thin metal films in oxidation work are considered in the concluding chapter, along with a brief discussion on their use in kinetic and mechanistic studies. Research scientists and graduate students who are interested in the fundamentals of adsorption and catalysis will find this volume invaluable.


Chemisorption of Probe Molecules

Chemisorption of Probe Molecules

Author:

Publisher: Elsevier

Published: 1990-07-19

Total Pages: 409

ISBN-13: 0080887473

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The present volume concentrates on catalyst surfaces. The interaction of adsorbed molecules, mostly on heterogenous catalysts, although some reference to model catalysts is also made, is discussed here. Vibrational (infrared and electron energy loss spectroscopies, magnetic resonances (nuclear and electron spin) and thermal desorption methods have been included in this latter category. The reader will find also a comparison of these well established methods with their recent developments which make them much more attractive. Therefore, researchers working in the catalysis field will find much to interest them in this book.


Green-Function Theory of Chemisorption

Green-Function Theory of Chemisorption

Author: Sydney G. Davison

Publisher: Springer Science & Business Media

Published: 2006-11-05

Total Pages: 223

ISBN-13: 1402044054

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Prefaces are like speeches before the c- tain; they make even the most self-forgetful performers seem self-conscious. — William Allen Neilson The study of phenomena and processes at the phase boundaries of m- ter is the realm of the surface scientist. The tools of his trade are drawn from across the spectrum of the various scienti?c disciplines. It is therefore interesting that, in investigating the properties of such boundaries, the s- facist must transcend the interdisciplinary boundaries between the subjects themselves. In this respect, he harkens back to the days of renaissance man, when knowledge knew no boundaries, and was pursued simply for its own sake, in the spirit of enlightenment. Chemisorption is a gas-solid interface problem, involving the inter- tion of a gas atom with a solid surface via a charge-transfer process, during which a chemical bond is formed. Because of its importance in such areas as catalysis and electronic-device fabrication, the subject of chemisorption is of interest to a wide range of surfacists in physics, chemistry, materials science, as well as chemical and electronic engineering. As a result, a vast lite- ture has been created, though, despite this situation, there is a surprising scarcity of books on the subject. Moreover, those that are available tend to be experimentally oriented, such as, Chemisorption: An Experimental - proach (Wedler 1976). On the theoretical side, The Chemisorption Bond (Clark 1974) provides a good introduction, but is limited in not describing the more advanced techniques presently in use.


Chemisorption And Reactions On Metallic Films V1

Chemisorption And Reactions On Metallic Films V1

Author: J Anderson

Publisher: Elsevier

Published: 2012-12-02

Total Pages: 568

ISBN-13: 0323145698

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Chemisorption and Reactions on Metallic Films, Volume 1 is a six-chapter text that describes the role of evaporated metal films in advancing the understanding of the metal-gas interface chemistry. Chapter 1 presents electron microscopy and diffraction studies and their contributions in elucidating the growth and structure of polycrystalline and epitaxially grown films. Chapter 2 describes the techniques of preparation and characterization of metallic films and examines the heats of adsorption, electrical conductivity, surface area, and sticking probabilities of such films. Chapter 3 discusses the strength of pairwise interactions; the influence of the intermetallic bond on the equilibrium shape of metal crystallites; the bonding of individual metal atoms to different crystallographic planes; the interaction of metal atoms and crystallites with non-conducting substrates; and the effects of residual gases on this interaction. Chapters 4 and 5 address the adsorption of metallic films, with an emphasis on general trends in adsorptive and electronic properties of bulk metals. These chapters also discuss the effects of adsorption on the electrical conductance of island-like and coherent films and on the ferromagnetic properties of films. Chapter 6 evaluates the application of infrared spectroscopy to the studies of the surfaces of metal films and the use of the available infrared spectroscopic data in reconciling the results of adsorption studies on oxide-supported metal particles with those obtained with clean evaporated metal films prepared under ultra high vacuum conditions. Research scientists and graduate students who are interested in the fundamentals of adsorption and catalysis will find this volume invaluable.