Electron Scattering With Molecules - A Theoretical Study


Book Description

Scattering of electrons is a fundamental phenomenon occurring either as a primary or secondary process whenever ionizing radiation interacts with matter. Energy deposition models, to study the interaction of radiation with matter and radiation damage, require scattering cross section data for all possible processes. Knowledge of electron scattering cross sections is therefore the most important and indispensable tool for the quantitative analysis of radiation impact phenomena. Electron impact ionization cross sections find practical applications in many branches of science viz. fusion edge plasmas, gas discharge plasmas, planetary, stellar and cemetery atmosphere, radiation chemistry, mass spectrometry and chemical analysis. Important applications of the basic knowledge of these collision processes include MHD (magneto hydrodynamics) power generation, electron lasers, the upper atmospheres of the earth and other planets and atmosphere of stars.




Low-Energy Electron Scattering from Molecules, Biomolecules and Surfaces


Book Description

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. F




Electron Scattering


Book Description

There is a unity to physics; it is a discipline which provides the most fundamental understanding of the dynamics of matter and energy. To understand anything about a physical system you have to interact with it and one of the best ways to learn something is to use electrons as probes. This book is the result of a meeting, which took place in Magdalene College Cambridge in December 2001. Atomic, nuclear, cluster, soHd state, chemical and even bio- physicists got together to consider scattering electrons to explore matter in all its forms. Theory and experiment were represented in about equal measure. It was meeting marked by the most lively of discussions and the free exchange of ideas. We all learnt a lot. The Editors are grateful to EPSRC through its Collaborative Computational Project program (CCP2), lOPP, the Division of Atomic, Molecular, Optical and Plasma Physics (DAMOPP) and the Atomic Molecular Interactions group (AMIG) of the Institute of Physics for financial support. The smooth running of the meeting was enormously facilitated by the efficiency and helpfulness of the staff of Magdalene College, for which we are extremely grateful. This meeting marked the end for one of us (CTW) of a ten-year period as a fellow of the College and he would like to take this opportunity to thank the fellows and staff for the privilege of working with them.




Variational Methods in Electron-Atom Scattering Theory


Book Description

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.







Atomic-Molecular Ionization by Electron Scattering


Book Description

Covers quantum scattering theories, experimental and theoretical calculations and applications in a comprehensive manner.




Collisions of Electrons with Atoms and Molecules


Book Description

This book is a short outline of the present state of the theory of electron collisions with atomic particles - atoms, molecules and ions. It is addressed to those who by nature of their work need detailed information about the cross sections of various processes of electron collisions with atomic particles: experimentalists working in plasma physics, optics, quantum electronics, atmospheric and space physics, 'etc. Some of the cross sections have been measured. But in many important cases the only source of information is theoretical calcu lation. The numerous theoretical papers dealing with electronic collision processes contain various approximations. The inter relation between them and the level of their accuracy is often diffi cult to understand without a systematic study of the theory of atomic collisions, not to mention that theoretical considerations are necessary for the consistent interpretation of experimental results. The main constituents of the book are: 1. General theory with special emphasis on the topics most impor tant for understanding and discussing electron collisions with atomic particles.




Electron-Atom and Electron-Molecule Collisions


Book Description

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.




Photon and Electron Collisions with Atoms and Molecules


Book Description

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.




Electron-Molecule and Photon-Molecule Collisions


Book Description

The First Asilomar Conference on Electron- and Photon-Molecule Collisions was held August 1-4, 1978 in Pacific Grove, California. This meeting brought together forty scientists who are actively involved in theoretical studies of electron scattering by, and photoionization of, small molecules. In this volume, are collected the contributions of the invited speakers, as well as the roundtable and evening discussions condensed from taped recordings of the entire proceedings. The subject matter reflects current activity in the field and describes many of the techniques that are being developed and applied to molecular collision problems. We would like to thank the Air Force Office of Scientific Research (AFOSR) and the Office of Naval Research (ONR) for providing the financial support that made this conference possible. Special thanks are due to Dr. Robert Junker of ONR and Dr. Ralph Kelley of AFOSR for the interest and encouragement they provided in all phases of this meeting. We also thank all the participants whose efforts and contributions made this conference a success. Finally, we thank Ms. Charlotte MacNaughton and Ms. Sara Jackson for the many hours they spent transcribing tapes and preparing this volume for publication.