Variational Methods In Electron Atom Scattering Theory

Author : Robert K. Nesbet
Publisher : Springer Science & Business Media
Page : 234 pages
File Size : 50,7 Mb
Release : 2013-11-21
Category : Science
ISBN : 9781468484311

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Variational Methods in Electron-Atom Scattering Theory by Robert K. Nesbet Pdf

The investigation of scattering phenomena is a major theme of modern physics. A scattered particle provides a dynamical probe of the target system. The practical problem of interest here is the scattering of a low energy electron by an N-electron atom. It has been difficult in this area of study to achieve theoretical results that are even qualitatively correct, yet quantitative accuracy is often needed as an adjunct to experiment. The present book describes a quantitative theoretical method, or class of methods, that has been applied effectively to this problem. Quantum mechanical theory relevant to the scattering of an electron by an N-electron atom, which may gain or lose energy in the process, is summarized in Chapter 1. The variational theory itself is presented in Chapter 2, both as currently used and in forms that may facilitate future applications. The theory of multichannel resonance and threshold effects, which provide a rich structure to observed electron-atom scattering data, is presented in Chapter 3. Practical details of the computational implementation of the variational theory are given in Chapter 4. Chapters 5 and 6 summarize recent appli cations of the variational theory to problems of experimental interest, with many examples of the successful interpretation of complex structural fea tures observed in scattering experiments, and of the quantitative prediction of details of electron-atom scattering phenomena.

Author : P. G. Burke
Publisher : Springer Science & Business Media
Page : 137 pages
File Size : 40,9 Mb
Release : 2012-12-06
Category : Science
ISBN : 9781461341123

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Potential Scattering in Atomic Physics by P. G. Burke Pdf

This monograph was written while the author was a visitor at the Center for Theoretical Studies at the University of Miami, Coral Gables, Florida. The author wishes to thank Professor Behram Kursunoglu for the warm hospitality extended to him at the Center and to acknowledge the many interesting and fruitful discussions which he had with other visitors and with members of staff at the Center. Philip G. Burke v Contents 1. Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 2. Scattering by a Short-Range Potential. . . . . . . . . . . . . . . 5 3. Scattering by a Coulomb Potential. . . . . . . . . . . . . . . . . . 11 4. Scattering by a Spin-Orbit Potential . . . . . . . . . . . . . . " 17 5. Scattering by One-Electron Atoms. . . . . . . . . . . . . . . . . . 23 6. Low-Energy Effective-Range Theory. . . . . . . . . . . . . . . . 39 7. Bound States and Resonances. . . . . . . . . . . . . . . . . . . . . . 55 8. Variational Methods and Bound Principles. . . . . . . . . . 75 9. Integral Equation Methods and the Born Approximation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97 10. Semiclassical and Eikonal Methods . . . . . . . . . . . . . . . . . 117 Appendix. The Coupling of Angular Momenta . . . . . . . . . . . 127 References. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131 Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135 vii 1 Introduction In this monograph we study the scattering of a particle by a potential field with particular reference to elastic electron scat tering by a neutral atom or by an ion. This subject is clearly of interest in its own right as a branch of quantum mechanical scattering theory. However, it also serves as an introduction to many of the basic theoretical concepts which are used in inelastic electron scattering and ionization. Consequently this mono graph can be viewed as an introduction to texts where these subjects are treated.

Author : Philip G. Burke,Charles J. Joachain
Publisher : Springer Science & Business Media
Page : 264 pages
File Size : 55,8 Mb
Release : 2013-06-29
Category : Science
ISBN : 9781489915672

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Theory of Electron—Atom Collisions by Philip G. Burke,Charles J. Joachain Pdf

The authors aim to hone the theory of electron-atom and electron-ion collisions by developing mathematical equations and comparing their results to the wealth of recent experimental data. This first of three parts focuses on potential scattering, and will serve as an introduction to many of the concepts covered in Parts II and III. As these processes occur in so many of the physical sciences, researchers in astrophysics, atmospheric physics, plasma physics, and laser physics will all benefit from the monograph.

Author : Robert K. Nesbet
Publisher : Cambridge University Press
Page : 245 pages
File Size : 54,5 Mb
Release : 2002-11-14
Category : Science
ISBN : 9781139435697

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Variational Principles and Methods in Theoretical Physics and Chemistry by Robert K. Nesbet Pdf

This book brings together the essential ideas and methods behind applications of variational theory in theoretical physics and chemistry. The emphasis is on understanding physical and computational applications of variational methodology rather than on rigorous mathematical formalism. The text begins with an historical survey of familiar variational principles in classical mechanics and optimization theory, then proceeds to develop the variational principles and formalism behind current computational methodology for bound and continuum quantum states of interacting electrons in atoms, molecules, and condensed matter. It covers multiple-scattering theory, including a detailed presentation of contemporary methodology for electron-impact rotational and vibrational excitation of molecules. The book ends with an introduction to the variational theory of relativistic fields. Ideal for graduate students and researchers in any field that uses variational methodology, this book is particularly suitable as a backup reference for lecture courses in mathematical methods in physics and theoretical chemistry.

Author : Jürgen Hinze
Publisher : Springer Science & Business Media
Page : 353 pages
File Size : 44,6 Mb
Release : 2013-11-11
Category : Science
ISBN : 9781489921482

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Electron-Atom and Electron-Molecule Collisions by Jürgen Hinze Pdf

The papers collected in this volume have been presented during a workshop on "Electron-Atom and Molecule Collisions" held at the Centre for Interdisciplinary Studies of the University of Bielefeld in May 1980. This workshop, part of a larger program concerned with the "Properties and Reactions of Isolated Molecules and Atoms," focused on the theory and computational techniques for the quanti tative description of electron scattering phenomena. With the advances which have been made in the accurate quantum mechanical characterisation of bound states of atoms and molecules, the more complicated description of the unbound systems and resonances important in electron collision processes has matured too. As expli cated in detail in the articles of this volume, the theory for the quantitative explanation of elastic and inelastic electron molecule collisions, of photo- and multiple photon ionization and even for electron impact ionization is well developed in a form which lends itself to a complete quantitative ab initio interpretation and pre diction of the observable effects. Many of the experiences gained and the techniques which have evolved over the years in the com putational characterization of bound states have become an essential basis for this development. To be sure, much needs to be done before we have a complete and detailed theoretical understanding of the known collisional processes and of the phenomena and effects, which may still be un covered with the continuing refinement of the experimental tech niques.

Author : R. Glowinski,A. Lichnewsky
Publisher : SIAM
Page : 464 pages
File Size : 46,5 Mb
Release : 1990-01-01
Category : Science
ISBN : 0898712645

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Computing Methods in Applied Sciences and Engineering by R. Glowinski,A. Lichnewsky Pdf

"Proceedings of the Ninth International Conference on Computing Methods in Applied Sciences and Engineering, Paris, France, January 29-February 2, 1990"--T.p. verso.

Author : Jean-Louis Calais,Eugene S. Kryachko
Publisher : Springer Science & Business Media
Page : 562 pages
File Size : 40,9 Mb
Release : 2012-12-06
Category : Science
ISBN : 9789401155724

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Conceptual Perspectives in Quantum Chemistry by Jean-Louis Calais,Eugene S. Kryachko Pdf

The rivers run into the sea, yet the sea is not full Ecclesiastes What is quantum chemistry? The straightforward answer is that it is what quan tum chemists do. But it must be admitted, that in contrast to physicists and chemists, "quantum chemists" seem to be a rather ill-defined category of scientists. Quantum chemists are more or less physicists (basically theoreticians), more or less chemists, and by large, computationists. But first and foremost, we, quantum chemists; are conscious beings. We may safely guess that quantum chemistry was one of the first areas in the natural sciences to lie on the boundaries of many disciplines. We may certainly claim that quantum chemists were the first to use computers for really large scale calculations. The scope of the problems which quantum chemistry wishes to answer and which, by its unique nature, only quantum chemistry can answer is growing daily. Retrospectively we may guess that many of those problems meet a daily need, or are say, technical in some sense. The rest are fundamental or conceptual. The daily life of most quantum chemists is usually filled with grasping the more or less technical problems. But it is at least as important to devote some time to the other kind of problems whose solution will open up new perspectives for both quantum chemistry itself and for the natural sciences in general.

Author : Anonim
Publisher : Unknown
Page : 938 pages
File Size : 52,8 Mb
Release : 1976-03
Category : Nuclear energy
ISBN : PSU:000047758889

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Nuclear Science Abstracts by Anonim Pdf

Author : Petr Carsky,Roman Curik
Publisher : CRC Press
Page : 296 pages
File Size : 40,6 Mb
Release : 2016-04-19
Category : Science
ISBN : 9781439839119

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Low-Energy Electron Scattering from Molecules, Biomolecules and Surfaces by Petr Carsky,Roman Curik Pdf

Since the turn of the 21st century, the field of electron molecule collisions has undergone a renaissance. The importance of such collisions in applications from radiation chemistry to astrochemistry has flowered, and their role in industrial processes such as plasma technology and lighting are vital to the advancement of next generation devices. Furthermore, the development of the scanning tunneling microscope highlights the role of such collisions in the condensed phase, in surface processing, and in the development of nanotechnology. Low-Energy Electron Scattering from Molecules, Biomolecules and Surfaces highlights recent progress in the theory and experiment of electron-molecule collisions, providing a detailed review of the current state of knowledge of electron molecule scattering—theoretical and experimental—for the general physicist and chemist interested in solving practical problems. In few other branches of science is the collaboration between theorists and experimentalists so topical. Covering advancements in practical problems, such as those met in plasma physics, microelectronics, nanolithography, DNA research, atmospheric chemistry, and astrochemistry, this book describes the formal general scattering theory and description of the experimental setup at a level the interested non-expert can appreciate.

Author : Isao Shimamura,Kazuo Takayanagi
Publisher : Springer Science & Business Media
Page : 578 pages
File Size : 43,7 Mb
Release : 2013-11-11
Category : Science
ISBN : 9781461323570

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Electron-Molecule Collisions by Isao Shimamura,Kazuo Takayanagi Pdf

Scattering phenomena play an important role in modern physics. Many significant discoveries have been made through collision experiments. Amongst diverse kinds of collision systems, this book sheds light on the collision of an electron with a molecule. The electron-molecule collision provides a basic scattering problem. It is scattering by a nonspherical, multicentered composite particle with its centers having degrees of freedom of motion. The molecule can even disintegrate, Le., dissociate or ionize into fragments, some or all of which may also be molecules. Although it is a difficult problem, the recent theoretical, experimental, and computational progress has been so significant as to warrant publication of a book that specializes in this field. The progress owes partly to technical develop ments in measurements and computations. No less important has been the great and continuing stimulus from such fields of application as astrophysics, the physics of the earth's upper atmosphere, laser physics, radiation physics, the physics of gas discharges, magnetohydrodynamic power generation, and so on. This book aims at introducing the reader to the problem of electron molecule collisions, elucidating the physics behind the phenomena, and review ing, to some extent, up-to-date important results. This book should be appropri ate for graduate reading in physics and chemistry. We also believe that investi gators in atomic and molecular physics will benefit much from this book.

Author : Philip G. Burke,Charles J. Joachain
Publisher : Springer Science & Business Media
Page : 384 pages
File Size : 51,8 Mb
Release : 2012-12-06
Category : Science
ISBN : 9781461559177

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Photon and Electron Collisions with Atoms and Molecules by Philip G. Burke,Charles J. Joachain Pdf

Research on photon and electron collisions with atomic and molecular targets and their ions has seen a rapid increase in interest, both experimentally and theoretically, in recent years. This is partly because these processes provide an ideal means of investigating the dynamics of many particle systems at a fundamental level and partly because their detailed understanding is required in many other fields, particularly astrophysics, plasma physics and controlled thermonuclear fusion, laser physics, atmospheric processes, isotope separation, radiation physics and chemistry and surface science. In recent years a number of important advances have been made, both on the experimental side and on the theoretical side. On the experimental side these include absolute measurements of cross sections, experiments using coincidence techniques, the use of polarised beams and targets, the development of very high energy resolution electron beams, the use of synchrotron radiation sources and ion storage rings, the study of laser assisted atomic collisions, the interaction of super-intense lasers with atoms and molecules and the increasing number of studies using positron beams.

Author : Franco A. Gianturco,W.M. Huo
Publisher : Springer Science & Business Media
Page : 374 pages
File Size : 53,8 Mb
Release : 2013-06-29
Category : Science
ISBN : 9781475797978

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Computational Methods for Electron—Molecule Collisions by Franco A. Gianturco,W.M. Huo Pdf

The collision of electrons with molecules and molecular ions is a fundamental pro cess in atomic and molecular physics and in chemistry. At high incident electron en ergies, electron-molecule collisions are used to deduce molecular geometries, oscillator strengths for optically allowed transitions, and in the case of electron-impact ionization, to probe the momentum distribution of the molecule itself. When the incident electron energy is comparable to or below those of the molecular valence electrons, the physics involved is particularly rich. Correlation and exchange effects necessary to describe such collision processes bear a close resemblance to similar efft:cts in the theory of electronic structure in molecules. Compound state formations, in the form of resonances and vir tual states, manifest themselves in experimental observables which provide details of the electron-molecule interactions. Ro-vibrational excitations by low-energy electron collisions exemplify energy transfer between the electronic and nuclear motion. The role of nonadiabatic interaction is raised here. When the final vibrational state is in the continuum, molecular dissociation occurs. Dissociative recombination and dissociative attachment are examples of such fragmentation processes. In addition to its fundamental nature, the study of electron-molecule collisions is also motivated by its relation to other fields of study and by its technological appli cations. The study of planetary atmospheres and the interstellar medium necessarily involve collision processes of electrons with molecules and molecular ions.

Author : John Nuttall
Publisher : London, Ont. : Department of Physics, University of Western Ontario
Page : 246 pages
File Size : 52,8 Mb
Release : 1978
Category : Nuclear physics
ISBN : UOM:39015017212294

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Atomic Scattering Theory by John Nuttall Pdf

Author : U Fano
Publisher : Elsevier
Page : 420 pages
File Size : 40,7 Mb
Release : 2012-12-02
Category : Technology & Engineering
ISBN : 9780323151115

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Atomic Collisions and Spectra by U Fano Pdf

Atomic Collisions and Spectra provides an overview of the state of knowledge on atomic collision physics. The book grew out of lecture notes for a succession of courses at the University of Chicago in 1967-1979, which reported the new material as it was taking a definite form. It has been enriched since 1980, as the subject matured and continued to expand. The book is organized into four parts. Part A deals briefly with rather elementary items of general information. Part B then takes up in considerable detail those aspects of single-electron scattering whose mastery is essential for treating multielectron processes. Part C deals with multielectron processes with a residual—if often realistic—restriction, namely, that the multielectron interactions remain confined within a core region from which only a single electron escapes into alternative channels of a long-range field. Part D surveys studies of double (or multiple) escape of electrons from a core. The book is intended for multiple use as a graduate school text, a tool for independent study, or a reference for particular topics.

Author : United States. Energy Research and Development Administration. Technical Information Center
Publisher : Unknown
Page : 1066 pages
File Size : 53,8 Mb
Release : 1977
Category : Force and energy
ISBN : MSU:31293010869604

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ERDA Energy Research Abstracts by United States. Energy Research and Development Administration. Technical Information Center Pdf