The demand for selective organic reactions is growing more acute everyday. Indeed, greater product selectivity has an important impact on energy and resource utilization, in terms of reduced process energy requirements for product separation and purification, in terms of low-value by-products, and in terms of environmental acceptance and compatibility. Moreover, more and more chemicals, especially pharmaceuticals, have to be sold in an optically active form. The search for selectivity constitutes a tremendous challenge for the chemists. In the last two decades, homogeneous transition metal based catalysis has emerged as one of the most promising tools for obtaining selectivity. In connection with developments in this area, this book contains updated and expanded versions of most of the lectures presented at a Cornett course held in Trieste (Italy) in 1989 and sponsored by the European Community. A primary aim is to cultivate a deeper understanding of the parameters that govern the selectivities and stimulate a wider utilization of transition metal based catalysis in organic synthesis. All aspects of selectivity, chemo-, regio-, stereo- and enantioselectivity are considered and illustrated by applications in various fields or organic synthesis. The impact of catalysis in oxydation, reduction, carbonylation reactions, carbene chemistry, in Ni and Pd promoted dimerizations, oligomerizations as well as fonctionalisations is stressed, quite often with special emphasis laid on reaction mechanisms. In this aspect, the last chapter examplifies the interest of high pressure NMR and IR when investigating the nature of reaction intermediates in homogeneous reactions.

This book contains a series of papers and abstracts from the 7th Industry-University Cooperative Chemistry Program symposium held in the spring of 1989 at Texas A&M University. The symposium was larger than previous IUCCP symposia since it also celebrated the 25 years that had elapsed since the initial discovery by F. A. Cotton and his co-workers of the existence of metal-metal quadruple bonds. Cotton's discovery demonstrated that multiple bonding in inorganic systems is not governed by the same constraints observed in organic chemistry regarding s and p orbital involvement. The d orbitals are involved in the multiple bonding description. The quadruple bond involves considerable d orbital overlap between adjacent metal centers. Part I of this series of papers focuses upon the impact of this discovery and describes further contributions to the development of the field. Multiple metal-metal bonding now is known to permeate broad areas of transition metal chemistry. The understanding of metal-metal bonding that developed as a result of the discovery of multiple metal-metal bonding awakened a new chemistry involving metal clusters. Clusters were defined by Cotton to be species containing metal-metal bonding. Clusters in catalysis therefore seemed a logical grouping of papers in this symposium. Clusters play an every increasing role in the control of chemical reactions. Part II of this book describes some of the interesting new developments in this field. In Part III the papers examine the role clusters play in describing and understanding solid state materials.

From boyhood in the coal-mining village of Coello, Illinois, to winning the Priestly Medal and becoming the president of the American Chemical Society, Professor Emeritus Fred Basolo of Northwestern University traces the intertwined development of his life, career, and the field of inorganic chemistry. With over a hundred photographs and dozens of structures and equations, From Coello to Inorganic Chemistry details the major innovations, travels, family life, and guests hosted while helping to build one of the world's leading inorganic chemistry departments from its humble beginnings at Northwestern University. Students and chemists with interests in bioinorganic chemistry, catalysis, nanoscience, new materials research, and organometallics can follow the emergence of inorganic chemistry as a rival to organic chemistry through the accomplishments of one of its most influential pioneers.

Most organic molecules retain their integrity when dissolved, and even though in such cases the effects exerted by solvents are, in the language of the coordination chemist, of the "outer sphere" kind, the choice of solvent can be critical to the successful outcome of an operation or preparation. Solubilities of reactants and products must be taken into account, and even if the organic principals in the reactions retain their integrity, many of the reagents are electrolytes, and their state of aggregation will affect their reactivity. In testifying to the importance of understanding solute-solvent interactions I draw attention to a large class of inorganic species for which the involvement in the chemical and physical properties by the solvent is even more deeply seated. It is comprised by the large body of metal atoms in low oxidation states for which solvent molecules intervene as reagents. At the same time, because the ions carry charges, the effects arising from outer sphere interactions are usually greater than they are for neutral molecules. To cite an example: when FeCb(s) is dissolved in water to form a dilute - say O. OlO- solution there is a complete reorganization of the coordination sphere of the cation. Whereas in the solid each cation is surrounded by six chloride ions, in the solution the dominant form is [Fe(H20)6]3+ followed by [Fe(H20)sCI]2+, [Fe(H20)4CI2]+, etc. in rapidly decreasing abundance.

This book is about how to avoid the accidents and injuries that may occur when batteries are abused or mishandled. It is the first book to deal specifically with this subject in a reasonably comprehensive manner accessible to readers ranging from regular consumers to technical specialists. Batteries and battery processes are described in sufficient detail to enable readers to understand why and how batteries cause accidents and what can be done to prevent them. Each year in the United States alone, thousands of individuals are injured by battery accidents, some of which are severely disabling. The tragedy is that such accidents need not occur. The book is intended to satisfy the needs of a varied group of readers: battery users in general, battery engineers, and designers of battery-operated equipment and consumer electronics. Since the book is a reference source of information on batteries and battery chemicals, we believe it may also be useful to those studying the environment as well as to medical personnel called upon to treat battery injuries. There are no prerequisites for an under standing of the text other than an interest in batteries and their safe usage.

P.J. van der Put offers students an original introduction to materials chemistry that integrates the full range of inorganic chemistry. Technologists who need specific chemical facts to manipulate matter will also find this work invaluable as an easy-to-use reference. The text includes practical subjects of immediate use for materials such as bonding, morphogenesis, and design that more orthodox materials science volumes often leave out.

"Imagination and shrewd guesswork are powerful instruments for acquiring scientific knowledge . . . " 1. H. van't Hoff The last decades have witnessed a rapid growth of quantum chemistry and a tremendous increase in the number of very accurate ab initio calculations of the electronic structure of molecules yielding results of admirable accuracy. This dramatic progress has opened a new stage in the quantum mechanical description of matter at the molecular level. In the first place, highly accurate results provide severe tests of the quantum mecha nics. Secondly, modern quantitative computational ab initio methods can be synergetically combined with various experimen tal techniques thus enabling precise numerical characterization of molecular properties better than ever anticipated earlier. However, the role of theory is not exhausted in disclosing the fundamental laws of Nature and production of ever increasing sets of data of high accuracy. It has to provide additionally a means of systematization, recognition of regularities, and ratio nalization of the myriads of established facts avoiding in this way complete chaos. Additional problems are represented by molecular wavefunctions provided by the modern high-level computational quantum chemistry methods. They involve, in principle, all the information on molecular system, but they are so immensely complex that can not be immediately understood in simple and physically meaningful terms. Both of these aspects, categorization and interpretation, call for conceptual models which should be preferably pictorial, transparent, intuitively appealing and well-founded, being sometimes useful for semi quantitative purposes."

Environmental Chemistry is a relatively young science. Interest in this subject, however, is growing very rapidly and, although no agreement has been reached as yet about the exact content and limits of this interdisciplinary subject, there appears to be increasing interest in seeing environmental topics which are based on chemistry embodied in this subject. One of the first objectives of Environ mental Chemistry must be the study of the environment and of natural chemical processes which occur in the environment. A major purpose of this series on Environmental Chemistry, therefore, is to present a reasonably uniform view of various aspects of the chemistry of the environment and chemical reactions occuring in the environment. The industrial activities of man have given a new dimension to Environ mental Chemistry. We have now synthesized and described over five million chemical compounds and chemical industry produces about one hundred and fifty million tons of synthetic chemicals annually. We ship billions of tons of oil per year and through mining operations and other geophysical modifications, large quantities of inorganic and organic materials are released from their natural deposits. Cities and metropolitan areas of up to 15 million inhabitants produce large quantities ofwaste in relatively small and confined areas. Much of the chemical products and was te products of modern society are released into the environment either during production, storage, transport, use or ultimate disposal. These released materials participate in natural cycles and reactions and frequently lead to interference and disturbance of natural systems."

Over the past fifteen years the Commission on Equilibrium Data of the Analytical Division of the I nter national Union of Pure and Applied Chemistry has been sponsoring a noncritical compilation of metal complex formation constants and related equilibrium constants. This work was extensive in scope and resulted in the publication of two large volumes of Stability Constants by the Chemical Society (London). The first volume, edited by L. G. Si"en (for inorganic ligands) and by A. E. Marte" (for organic ligands), was published in 1964 and covered the literature through 1962. The second volume, subtitled Supplement No.1, edited by L. G. Si"en and E. Hogfeldt (for inorganic ligands) and by A. E. Marte" and R. M. Smith (for organic ligands), was published in 1971 and covered the literature up to 1969. These two large compilations attempted to cover a" papers in the field related to metal complex equilibria (heats, entropies, and free energies). Since it was the policy of the Commission during that period to avoid decisions concerning the quality and reliability of the published work, the compilation would frequently contain from ten to twenty values for a single equilibrium constant. In many cases the values would differ by one or even two orders of magnitude, thus frustrating readers who wanted to use the data without doing the extensive literature study necessary to determine the correct value of the constant in question."

Bioinorganic Chemistry of Copper focuses on the vital role of copper ions in biology, especially as an essential metalloenzyme cofactor. The book is highly interdisciplinary in its approach--the outstanding list of contributors includes coordination chemists, biochemists, biophysicists, and molecular biologists. Chapters are grouped into major areas of research interest in inorganic copper chemistry, spectroscopy, oxygen chemistry, biochemistry, and molecular biology. The book also discusses basic research of great potential importance to pharmaceutical scientists. This book is based on the first Johns Hopkins University Copper Symposium, held in August 1992. Researchers in chemistry, biochemistry, molecular biology, and medicinal chemistry will find it to be an essential reference on its subject.

Asphaltenes have traditionally been viewed as being extremely complex, thus very hard to characterize. In addition, certain fundamental properties of asphaltenes have pre viously been inaccessible to study by traditional macroscopic methods, further limiting understanding of asphaltenes. These limitations inhibited development of descriptions regarding the microscopic structure and solution dynamics of asphaltenes. However, a variety ofmore recent studies have implied that asphaltenes share many chemical properties with the smaller, more tractable components of crude oils. Recent measurements have indicated that asphaltene molecular weights are not as arge as previously thought, perhaps in the range of 600 to I 000 amu. In addition, new experimental methods applied to asphaltene chemical structures have been quite revealing, yielding a broad understanding. Conse quently, the ability to relate chemical structure with physical and chemical properties can be developed and extended to the understanding of important commercial properties of asphal tenes. This book treats significant new developments in the fundamentals and applications of asphaltenes. In the first section ofthe book, new experimental methods are described that characterize asphaltene structures from the molecular to colloidallength scale. The colloidal properties are understandable in terms of asphaltene chemical structures, especially with regard to the heteroatom impact on bonding. However, quantitative measurements of the of asphaltene self-association still need to be determined. In the second section of enthalpy this book, the fundamental understanding of asphaltenes is related riirectly to asphaltene utilization."

The fields of hydrodesulfurization (HDS) and hydrodenitrogenation (HDN) continue to attract the attention of researchers in the various disciplines connected to these fascinating problems that represent two of the key outstanding chemical challenges for the petroleum refining industry in view of their very strong environmental and commercial implications. One area that has flourished impressively over the last 15 years is the organometallic chemistry of thiophenes and other related sulfur-containing molecules. This has become a powerful method for modeling numerous surface species and reactions implicated in HDS schemes, and nowadays it represents an attractive complement to the standard procedures of surface chemistry and heterogeneous catalysis, for understanding the complex reaction mechanisms involved in this process. Similar developments have begun to appear in connection with HDN mechanisms, although in a much more modest scale and depth. Some years ago when, encouraged by Prof. B. R. James, this book was planned, several excellent reviews and monographs treating different aspects of HDS were already available including some on the subject of organometallic models. However, it seemed appropriate to try to summarize the most striking features of this chemistry in an updated and systematic way, and inasmuch as possible in connection with the common knowledge and beliefs of the mechanisms of heterogeneous HDS catalysis. Hopefully, this attempt to build some conceptual bridges between these two traditionally separated areas of chemistry has met with some success.

During recent years a high level of interest has been maintained in the kinetics and mechanisms of inorganic compounds in solution, and there has also been a notable upsurge of literature concerned with reaction mechanisms of organo transition metal compounds. The reviews of the primary literature previously provided by "Inorganic Reaction Mechanisms" (Royal Society of Chemistry) and "Reaction Mechanisms in Inorganic Chemistry" in "MTP International Re views of Science" (Butterworths) continue to be of considerable value to those concerned with mechanistic studies, and it is unfortunate they are no longer published. The objective of the present series is to provide a continuing critical review of literature dealing with mechanisms of inorganic and organometallic reactions in solution. The scope of potentially relevant work is very large, particularly in the field of organotransition metal chemistry, and papers for inclusion have been chosen that specifically probe mechanistic aspects, rather than those of a prep arative nature. This volume covers the literature published during the period July 1979 to December 1980 inclusive. Material is arranged basically by type of reaction and type of compound along generally accepted lines. Numerical data are usually reported in the units used by the original authors, though the units of some results have been converted in order to make comparisons.

Microcharacterization of materials is a rapidly advancing field. Among the many electron and ion probe techniques, the cathodoluminescence mode of an electron probe instrument has reached a certain maturity, which is reflected by an increas ing number of publications in this field. The rapid rate of progress in applications of cathodoluminescence techniques in characterizing inorganic solids has been especially noticeable in recent years. The main purpose of the book is to outline the applications of cath odoluminescence techniques in the assessment of optical and electronic proper ties of inorganic solids, such as semiconductors, phosphors, ceramics, and min erals. The assessment provides, for example, information on impurity levels derived from cathodoluminescence spectroscopy, analysis of dopant concentra tions at a level that, in some cases, is several orders of magnitude lower than that attainable by x-ray microanalysis, the mapping of defects, and the determination of carrier lifetimes and the charge carrier capture cross sections of impurities. In order to make the book self-contained, some basic concepts of solid-state phys ics, as well as various cathodoluminescence techniques and the processes leading to luminescence phenomena in inorganic solids, are also described. We hope that this book will be useful to both scientists and graduate students interested in microcharacterization of inorganic solids. This book, however, was not intended as a definitive account of cathodoluminescence analysis of in organic solids. In considering the results presented here, readers should re member that many materials have properties that vary widely as a function of preparation conditions."

This and its companion Volume 2 chronicle the proceedings of the First Technical Conference on Polyimides: Synthesis, Char acterization and Applications held under the auspices of the Mid Hudson Section of the Society of Plastics Engineers at Ellenville, New York, November 10-12, 1982. In the last decade or so there has been an accelerated interest in the use of polyimides for a variety of applications in a number of widely differing technologies. The applications of polyimides range from aerospace to microelectronics to medical field, and this is attributed to the fact that polyimides offer certain desirable traits, inter alia, high temperature stability. Polyimides are used as organic insulators, as adhesives, as coat ings, in composites, just to name a few of their uses. Even a casual search of the literature will underscore the importance of this class of materials and the high tempo of R&D activity taking place in the area of polyimides. So it was deemed that a conference on polyimides was both timely and needed. This conference was designed to provide a forum for discussion of various ramifications of polyimides, to bring together scientists and technologists interested in all aspects of polyimides and thus to provide an opportunity for cross-pollination of ideas, and to highlight areas which needed further and intensi fied R&D efforts. If the comments from the attendees are a baro meter of the success of a conference, then this event was highly successful and fulfilled amply its stated objectives.

Cryogenics is an emerging technology filled with promises. Many cryogenic systems demand the use of nonmetallics and composites for adequate or increased performance. Thermal and electrical insulations, potting for superconducting magnets' mechanical sta bility, and composite structures appear to be some of the most significant applications. Research on nonmetallics at cryogenic temperatures has not progressed to the degree of research on metals. Nor can room temperature research be extrapolated to low tempera tures; most polymers undergo a phase transformation to the glassy state below room temperature. Research by producers, for the most part, has not been prac tical, because, except for LNG applications, the market for large material sales is not imminent. There are, however, many government stimulated developmental programs. Research on nonmetallics thus is dictated by development project needs, which require studies orien ted toward prototype hardware and specific objectives. As a result, research continuity suffers. Under these conditions, periodic topical conferences on this subject are needed. Industry and uni versity studies must be encouraged. Designers and project research material specialists need to exchange experiences and data. Low temperature-oriented research groups, such as the National Bureau of Standards and the Institute for Technical Physics - Karlsruhe, must contribute by assisting with fundamentals, interpreting proj ect data, and contributing to project programs through their materials research."

Syracuse University and the Army Materials and Mechanics Research Center of Watertown, Massachusetts have conducted the Sagamore Army Materials Research Conference since 1954. In ce1ebration of the 25th Anniversary of this conference, these proceedings are dedicated to the founding members of the Sagamore Conferences. They are Prof. Dr. George Sachs, Dr. James L. Martin, Colonel Benjamin S. Mesik, Dr. Reinier Beeuwkes, Mr. Norman L. Reed and Dr. J. D. Lubahn. This vo1ume, ADVANCES IN METAL PROCESSING, addresses Rapid Solidification Processing, Powder Processing and Conso1idation, We1ding and Joining, Thermal and. Mechanica1 Processing, Meta1 Removal and Process Mode1ing. The dedicated assistance of Mr. Joseph M. Bernier of the Army Materials and Mechanics Research Center and He1en Brown DeMascio of Syracuse University throughout the stages of the conference p1anning and fina11y the pub1ication of this book is deep1y appreciated. Syracuse University Syracuse, New York The Editors vii CONTENTS OVERVIEW Materials Processing - A Perspective of the Field 1 M.C. Flemings and R. Mehrabian SESSION I RAPID SOLIDIFICATION PROCESSING B.B. Rath, Moderator Heat Flow Limitations in Rapid Solidification Processing . . . . . . . . . . . 13 R. Mehrabian, S.C. Hsu, C.G. Levi, and S. Kou Laser Processing of Materials . . . . . 45 B.H. Kear, E.M. Breinan, and E.R. Thompson Electrohydrodynamic Techniques in Metals 79 Processing . . . . . . . . . . ."

"Relativistic Methods for Chemists," written by a highly qualified team of authors, is targeted at both experimentalists and theoreticians interested in the area of relativistic effects in atomic and molecular systems and processes and in their consequences for the interpretation of the heavy element's chemistry.

The theoretical part of the book focuses on the relativistic methods for molecular calculations discussing relativistic two-component theory, density functional theory, pseudopotentials and correlations. The experimentally oriented chapters describe the use of relativistic methods in different applications focusing on the design of new materials based on heavy element compounds, the role of the spin-orbit coupling in photochemistry and photobiology, and chirality and its relations to relativistic description of matter and radiation.

This book is written at an intermediate level in order to appeal to a broader audience than just experts working in the field of relativistic theory.

This book arose from a symposium titled 'Transition Metal Carbides and Nitrides: Preparation, Properties, and Reactivity' organized by Jae Sung Lee, Masatoshi Nagai and myself. The symposium was part of the 1995 Congress of Pacific Rim Chemical Societies, held in Honolulu, Hawaii between December 17-22, 1995. The meeting was the first major conference to exclusively address the theme of metal carbides and nitrides, and brought together many of the major researchers in the field. Over 50 scientists and engineers reported their latest findings in five sessions of presentations and discussions. The book closely follows the topics covered in the conference: Theory of bonding Structure and composition Catalytic properties Physical properties New methods of preparation Spectroscopy and microscopy The book is unique in its coverage. It provides a general introduction to the properties and nature of the materials, but also covers their latest applications in a wide variety of fields. It should thus be of interest to both experts and nonexperts in the fields of material science, solid-state chemistry, physics, ceramics engineering, and catalysis. The first chapter gives an overview, and many of the chapters provide summaries of advanced topics. All contributions were peer-reviewed.