In the last twenty years the literature on the processes of ionic polymerization has reached such a level that there is not a single question which is not covered by the information contained in the many monographs, reference books, and textbooks in this field. It is easy for the interested reader to find sources for in-depth study, for a superficial acquaintance with the fundamentals of the subject or with the general features of these processes. At the same time the field is being continually enriched by new facts which have not only broadened the data base but which influence existing concepts on the mechanisms of these reactions. Such influences often touch the very foundations of these concepts, i. e., they go beyond simple descriptions of the structure of the pre-reaction states or earlier schemes. It is therefore appropriate to attempt a critical appraisal of the modern views on the mechanisms of formation of macro molecules in ionic systems which envisages, so far as is possible, the differentiating of fundamental and hypothetical conclusions or concepts. With this in mind we have preferred to address ourselves to the reader who is already quite well acquainted with the general litera ture. This has allowed us to dispense with detailed introductions to the questions discussed and to limit ourselves to brief comments on the fundamentals of the subject."

The field of gas phase inorganic ion chemistry is relatively new; the early studies date back approximately twenty years, but there has been intense interest and development in the field in the last ten years. As with much of modern chemistry, the growth in gas phase inorganic ion chemistry can be traced to the development of instrumentation and new experimental methods. Studies in this area require sophisticated instruments and sample introduc tion/ ionization methods, and often these processes are complicated by the need for state-selecting (or collisionally stabilizing) the reactive species in order to assign the chemistry unequivocally. At the present level of experimental development, a wide range of experiments on diverse ionic systems are possible and many detailed aspects of the chemistry can be studied. Gas Phase Inorganic Chemistry focuses on the reactions of metal ions and metal clusters, and on the study of these species using the available modern spectroscopic methods. Three of the twelve chapters cover the chemistry of ionic monometal transition metal ions and the chemistry of these species with small diatomics and model organics. Two of the chapters focus on the studies of the chemical and physical properties of (primarily) transition metal clusters, and these chapters review experimental methods and capabilities. Two chapters also deal with the chemistry of transition metal carbonyl clusters, and these chapters address issues important to cluster growth and activation as well as the characterization of such species."

Electronic Properties of Fullerenes and other Novel Materials gives an overview of the state-of-the-art research. It presents most recent results on preparation, experimental analysis by electron spectroscopy, infrared and Raman spectroscopy, luminescence, and nonlinear optical, as well as possible technological applications. Emphasis is also placed on the superconducting properties of Fullerenes. The introductory and advanced contributions provide a good survey of the current status of this rapidly developing field.

There is no paucity of books on high pressure. Beginning with P. W. Bridgman's The Physics of High Pressure, books of general interest include the two-volume Physics and Chemistry of High Pressure, edited by R. S. Bradley, and the series, Advances in High Pressure Research, as well as the report on the Lake George Conference in 1960. Solid state physics is well represented by Solids Under Pressure, edited by Paul and Warschauer, by Physics of Solids at High Pressure, edited by Tomizuka and Emrick, and by Properties Physiques des Solides sous Pression, edited by Bloch, as well as by chapters in Volumes 6, 13, 17, and 19 of Solid State Physics, edited by Seitz, Turnbull, and Ehrenreich. Chemistry in gases and liquids is covered in Weale's Chemical Reactions at High Pressure, and Hamann's Physico-chemical Effects of Pressure. In addition to the coverage of techniques and calibrations in the above volumes, Modern Very High Pressure Techniques, edited by Wentorf, High Pressure Methods in Solid State Research, by C. C. Bradley, The Accurate Characterization of the High Pressure Environment, edited by E. C. Lloyd, and a chapter in Volume 11 of Solid State Physics are devoted entirely to this facet of high pressure research. It is not our plan either to supersede or extend these approaches. It is our purpose here to discuss the effect of high pressure on the electronic properties of solids.

Computational Chemistry, Volume 73, the latest release in the Advances in Inorganic Chemistry series, presents timely and informative summaries on current progress in a variety of subject areas. This acclaimed serial features reviews written by experts in the field, serving as an indispensable reference to advanced researchers that empowers readers to pursue new developments in each field. Users will find this to be a comprehensive overview of recent findings and trends from the last decade that covers various kinds of inorganic topics, from theoretical oriented supramolecular chemistry, to the quest for accurate calculations of spin states in transition metals.

Superalloys are unique high-temperature materials used in gas turbine engines, which display excellent resistance to mechanical and chemical degradation. This book presents the underlying metallurgical principles which have guided their development and practical aspects of component design and fabrication from an engineering standpoint. The topics of alloy design, process development, component engineering, lifetime estimation and materials behaviour are described, with emphasis on critical components such as turbine blading and discs. The first introductory text on this class of materials, it will provide a strong grounding for those studying physical metallurgy at the advanced level, as well as practising engineers. Included at the end of each chapter are exercises designed to test the reader's understanding of the underlying principles presented. Solutions for instructors and additional resources are available at www.cambridge.org/9780521859042.

This is a textbook of what is often called magnetochemistry. We take the point of view that magnetic phenomena are interesting because of what they tell us about chemical systems. Yet, we believe it is no longer tenable to write only about such subjects as distinguishing stereochemistry from the measurement of a magnetic susceptibility over a restricted temper ature region; that is, paramagnetism is so well-understood that little remains to explore which is of fundamental interest. The major purpose of this book is to direct chemists to some of the recent work of physicists, and in particular to a lengthy exposition of magnetic ordering phenomena. Chemists have long been interested in magnetic interactions in clusters, but many have shied away from long-range ordering phenomena. Now however more people are investigating magnetic behavior at temperatures in the liquid helium region, where ordering phenomena can scarcely be avoided. The emphasis is on complexes of the iron-series ions, for this is where most of the recent work, both experimental and theoretical, has been done. The discussion therefore is limited to insulating crystals; the nature of magnetism in metals and such materials as semiconductors is sufficiently different that a discussion of these substances is beyond our purposes. The book is directed more at the practical experimentalist than at the theoretician."

"Ionic liquids will never find application in industry", "I don't understand this fad for ionic liquids" and "there is no widespread interest in these systems" are just three of quotes from the reports of referees for research proposals that I have received over the years. I wonder what these people think today. There are currently at least nine large-scale industrial uses of ionic liquids, including, we now rec- nise, the production of ?-Caprolactam (a monomer for the production of nylon-6) [1]. There has been a steady increase in the interest in ionic liquids for well over a decade and last year the number of papers and patents including ionic liquids was counted in the thousands. This remarkable achievement has been built on the hard work and enthusiasm, first of a small band of devotees, but now of huge numbers of scientists all over the world who do not see themselves as specialists in ionic liquids. The ionic liquids field continues to develop at an incredible rate. No sooner do I think that I am on top of the literature than it turns out that a whole new area of work has emerged without me noticing. Things that were once supposedly impos- 1 sible in ionic liquids, such as measuring the H NMR of solutes, are now widely applicable (see Chapter 8). Hence, collected volumes such as this are very w- come.

A lively demonstration of the great vitality and the multidisciplinary character of cluster research and of the usefulness of synthesizing its various aspects was given at this symposium. This volume covers all aspects of the physical and chemical properties of free and supported clusters or small particles: static, dynamical, electronic, magnetic and optical properties, adsorption and chemical phenomena. It thus gives a complete overview of the status of the field and its development.

"Meditationis est perscrutari occulta; contemplationis est admirari perspicua . . . Admiratio generat qurestionem, qurestio investigationem, investigatio inventionem" once wrote HUGO DE S. VICTORE and possibly described best the life span of the rare earths since the Swedish Army Lieutenant, C. A. ARRHENIDS' discovery of an unusual black mineral at Ytterby in 1787. Since then the rare earths have passed through the machinery of various phases of physical science. Europium as a member of the rare earth family shows characteristics of the series as a whole as well as some typical behaviour of its own due to the presence of its six f electrons i. e. , one less than the half-filled shell. This present volume attempts to provide an understanding of the various aspects of its chemical and physical behaviour. In doing so, it is hoped to provide the reader with more than just a list of the complete bibliography on the subject, and I have tried to review the literature for it's interesting features, balancing the experimental facts with the help of the minimum amount of theory as far as possible. Experience has shown us that the trend of inorganic research has changed during the past years and one frequently needs some understanding of chemical spectroscopy and quantum mechanics to be able to appreciate the developments in this field and to interpret the wealth of experimental data. The reader is referred to B. G. WYBOURNE'S book: Spectroscopic Properties of Rare Earths (ref. [488]), and B. R.

During the course of far-infrared investigations of inorganic and coordina tion compounds at Argonne National Laboratory in the years 1962-1966, it became apparent that no suitable book existed which correlated and dis cussed the important vibrations occurring in this region for these molecules. Early in 1967 the initial steps were taken to write such a book. Then, in 1968, an excellent text by Professor David M. Adams entitled Metal-Ligand and Related Vibrations was published. At this point serious consideration was given to discontinuing work on this book. However, upon examination of Adams' book, it became clear that the references covered only the period to 1966. This field of research is accelerating so tremendously, and the period 1966-1969 has seen so many new studies, that upon reconsideration it was decided to continue writing this text. The references in this book, particularly in the last several chapters, include many papers published in 1969. However, the proliferation of the far-infrared literature has made it impossible to present all the published material that has any bearing on the subject. Many titles do not pertain primarily to the far-infrared region as such, and some of this research has been omitted for this reason. Organometallic compounds have been neglected since the author feels that adequate reviews of that subject are available. Other studies may be missing simply because, owing to space limitations, only the more important researches could be considered. Of course, "importance" may, in this case, reflect the author's interest and prejudices."

In every generation the achievements in science have served mankind. The progress accomplished by one generation stimulates the next generation to even greater achievements, which may take the form of increasing, crystallizing, or detailing existing theo- ries. Other forms, generally resulting from persistence and enlight- ened fortune, open new areas of investigation previously unimagined and have an impact that may be felt for many years. An example of this latter form of achievement was the prepara- tion and elucidation of the structures of dicyclopentadienyliron (ferrocene, reported in 1951) dibenzenechromium iodide, triphenyl- chromium tristetrahydrofuranate, and numerous olefin-metal -com- plexes which provided an introduction to new types of chemical bonds- the sigma carbon-transition metal bond and the metal -complex bond. Initial progress in the field of organotransition-metal chemis- try followed the lines of interest generated separately by organic and inorganic chemistry. However, it is becoming increasingly clear that organotransit10n-metal chemistry is not only bridging these two fields, but also crosslinking many other fields of science.

This book contains the papers and discussions from the sympo , ium on "The Catalytic Chemistry of Nitrogen Oxides" held at the General Motors Research Laboratories on October 7-8, 1974. This symposium is the eighteenth in the annual series presented by the Research Laboratories. The topics for these symposiums have covered a broad range. Each topic was selected to be of intense current interest and of significant technical importance. There is no question that the subject of the 1974 Symposium satisfies these two criteria. The control of automotive nitrogen oxides has been perhaps the most difficult and controversial area of automotive emissions both in terms of what is necessary and in terms of what is technically feasible. This area has been a source of considerable discussion not only in the technical community but also in governments both in the U. S. and abroad. This meeting brought together scientists working in surface chemistry with engineers working on system design. It also brought together representatives of government, academia and industry. We feel that an important side benefit of the meeting was the improved understanding that was developed between these groups. Participants came from Europe and Japan as well as Canada and the United States. The technical papers spanned the range from fundamental interactions of NO on surfaces through bench scale kinetic and mechanistic studies and ended with catalytic applications. Although the emphasis was on automotive NO removal, stack gas NO x x control was also covered.

It is now some sixteen years since the author's first series of books on the analysis of organometallic compounds. Many developments in the subject have occurred since that time and a new book on the subject is now overdue. The present book aims to provide a comprehensive review of the subject. It covers not only all aspects of the analysis of organometallic compounds but also contains two additional chapters, dealing with environmental analysis and the use of chelates of metals in the determination of very low concentrations of organic metals. Whilst reviewing the literature for the present book, it was observed that whereas papers published prior to 1973 dealt almost exclusively with various forms of analysis, a high proportion of those published during the past ten years were concerned with the application of proven or newly developed methods to the determination of organometallic compounds in environmental samples such as water, air, soil, river and ocean sediments, fish life and biota samples. An increasing range of elements including mercury, lead, arsenic, tin, antimony, selenium and manganese are now being found in organically bound forms in the environment, some resulting from pollution, others formed in nature by bacterial processes. As many of these substances have appreciable implications to human and animal health and the ecosystem as a whole, it was considered that it would be timely to include a separate chapter in the book devoted entirely to this subject.

The three natural streams of present-day chemistry are Structure, Dynamics and Synthesis and all these three elements are essential for the study of materials, particularly in the solid state. The solid state provides challenging opportunities for illustrating and applying principles of chemistry to systems of academic interest and technological importance. There are several practising solid state chemists in universities and research laboratories, but the subject has not yet become part of the formal training program in chemistry. Being one of the new frontiers of chemistry, Solid State Chemistry has a tremendous future and undoubtedly demands the active involvement of many more chemists. A Winter School in Solid State Chemistry was organized at the Indian Institute of Technology, Kanpur, to promote this area and to develop curricular material. Solid State Chemistry being lighly interdisciplinary in nature, the lecturers and participants at the Winter School had widely different backgrounds and interests. It was my great desire that the lecture material from the Winter School should become available to a larger body of students, teachers and research workers interested in the solid state and hence this volume.

Fundamental QSARs for Metal Ions describes the basic and essential applications of quantitative structure-activity relationships (QSARs) for regulatory or industrial scientists who need to predict metal ion bioactivity. It includes 194 QSARs that have been used to predict metal ion toxicity and 86 QSARs that have been used to predict metal ion bioconcentration, biosorption, and binding. It is an excellent sourcebook for academic, industrial, and government scientists and policy makers, and provides a wealth of information on the biological and chemical activities of metal ions as they impact health and the environment. Fundamental QSARs for Metal Ions was designed for regulatory and regulated organizations that need to use QSARs to predict metal ion bioactivity, as they now do for organic chemicals. It has the potential to eliminate resources to test the toxicity of metal ions or to promulgate regulations that require toxicity testing of metal ions because the book illustrates how to construct QSARs to predict metal ion toxicity. In addition, the book: Provides a historical perspective and introduction to developing QSARs for metal ions Explains the electronic structures and atomic parameters of metals essential to understanding differences in chemical properties that influence cation toxicity, bioconcentration, biosorption, and binding Describes the chemical properties of metals that are used to develop QSARs for metal ions Illustrates the descriptors needed to develop metal ion-ligand binding QSARs Discusses 280 QSARs for metal ions Explains the differences between QSARs for metal ions and Biotic Ligand Models Lists the regulatory limits of metals and provides examples of regulatory applications Illustrates how to construct QSARs for metal ions Dr. John D. Walker is the winner of the 2013 SETAC Government Service Award.

For a long time, the properties of transition metal and rare earth compounds have fascinated chemists and physicists from a scientific view-point, and more recently also their enormous potential as new materials has been explored. Applications in different fields have already been realized or are under c- rent investigation, for example, new laser materials, IR to visible upconversion systems, compounds for photolithographic processes, systems involving pho- redox processes for solar energy conversion, new photovoltaic devices, chemical sensors, biosensors, electroluminescent devices (OLEDs) for flat panel display systems, supramolecular devices with wide-range definable photophysical properties, materials for energy harvesting, optical information and storage systems, etc. Metal complexes are also highly important in biology and me- cine. Most of the applications mentioned are directly related to the properties of the electronic ground state and the lower-lying excited states. Metal complexes with organic ligands or organometallic compounds exhibit outstanding features as compared to purely organic molecules. For instance, metal compounds can often be prepared and applied in different oxidation states. Furthermore, various types of low-lying electronic excitations can be induced by a suitable choice of ligands, for example, such as metal-centered transitions (MC, e. g. d-d* tran- tion), ligand-centered (LC, e. g. n-n*), metal-to-ligand-charge transfer (MLCT, e. g. d-7r*), intra-ligand-charge-transfer (ILCT) transitions, etc. In particular, the orbitals involved in the resulting lowest excited states determine the photoph- ical and photochemical properties and thus the specific use of the compoun

When this book was first conceived as a project the expanding interest in the clinical use of platinum and gold complexes made a survey of the relevant biological properties of metal complexes timely and appropriate. This timeliness has not diminished during the gestation and final publica tion of the manuscript. The introduction contains an explanation of the layout and approach to the book, which I wrote as an overall survey of the wide variety of biological properties of metal complexes. Hopefully, the reader will see the parallels in mechanisms and behavior, even in different organisms. The writing was considerably helped by the enthusiasm and confidence (totally unearned on my part) in the project of Professor Brian James and lowe him my special thanks. I also owe a great debt of gratitude to my colleagues, and especially to Eucler Paniago, of the Universidade Federal de Minas Gerais, for their comprehension and for the initial leave of absence which allowed me to begin the project. To those who read some or all of the manuscript and made suggestions, Bernhard Lippert, Kirsten Skov, and Tom Tritton, as well as the editor's reviewer I am also grateful. As usual, the final responsibility for errors or otherwise rests with the author."

V. I. MATKOVICH During the meeting of the International Symposium on Boron held in October, 1972 in Tbilisi, U.S.S.R., the idea was proposed to assemble a review of boron and refractory borides by the specialists present. The advantages of such a work were immediately apparent. Such diverse applications of borides as in protective armor, nuclear reactors, coat ings, reinforcement, etc. can hardly all be presented in sufficient detail by a single author. On the other hand it was also recognized that with so much specialization, some areas of interest may not be covered. Within the last decade or two a number of areas have been developed in which the use of refractory borides is growing and improvements are being actively explored. Thus, a number of borides have considerable potential as reinforcing material for plastics or light metals, though only boron fibers have been firmly established up to the present. Ap plication of flakes and films for two-dimensional reinforcement appears attractive, although the high cost of materials and development repre sents a considerable barrier. A number of borides have been used to manufacture lightweight protec tive armor. In this area relatively fast changes seem to be taking place as improvements in performance and weight are made. Boron carbide has found considerable use in this application and new developments exploit the light weight of beryllium borides."

Recent developments in various areas of chemistry have been decisively influenced by the principles of structure and mechanism and by the ideas of coordination chemistry, in particular by the donor-acceptor approach, A unified view of almost all kinds of molecular forces is provided by quantum mechanics, and for practical purposes have been classified according to model assumptions, namely, dispersion, polarization, electrostatic, and short-range forces. The latter are divided into two- and three-center covalent chemical bonds, metallic bonds, and exchange-repulsion forces. This approach allows statements of principle and systematic analysis. However, quantitative predictions on concrete large systems are virtually impossible, and there are no general rules that account for structural and chemical changes due to intermolecular interactions. Chemists are therefore left with qualitative descriptions in which the changes in electron densities are considered. Such models as the MO theory or the resonance concept unrealistically assume that the nuclei remain in fixed positions. Further difficulties are encountered in the attempted description on the "nature" of the chemical bond, e.g., the forces involved. In order to avoid these difficulties an extension of the donor-acceptor concept, characterized by the comparison between equilibrium structures in different molecular environments, will be presented in this book. In this way, changes in the positions of the nuclei can be taken into account and the question of the nature of the molecular forces is no longer important.

Humans have been "manually" extracting patterns from data for centuries, but the increasing volume of data in modern times has called for more automatic approaches. Early methods of identifying patterns in data include Bayes' theorem (1700s) and Regression analysis (1800s). The proliferation, ubiquity and incre- ing power of computer technology has increased data collection and storage. As data sets have grown in size and complexity, direct hands-on data analysis has - creasingly been augmented with indirect, automatic data processing. Data mining has been developed as the tool for extracting hidden patterns from data, by using computing power and applying new techniques and methodologies for knowledge discovery. This has been aided by other discoveries in computer science, such as Neural networks, Clustering, Genetic algorithms (1950s), Decision trees (1960s) and Support vector machines (1980s). Data mining commonlyinvolves four classes of tasks: * Classi cation: Arranges the data into prede ned groups. For example, an e-mail program might attempt to classify an e-mail as legitimate or spam. Common algorithmsinclude Nearest neighbor,Naive Bayes classi er and Neural network. * Clustering: Is like classi cation but the groups are not prede ned, so the algorithm will try to group similar items together. * Regression: Attempts to nd a function which models the data with the least error. A common method is to use Genetic Programming. * Association rule learning: Searches for relationships between variables. For example, a supermarket might gather data of what each customer buys.

This volume contains a series of papers originally presented at the Symposium on Polymer Gels organized and sponsored by the Research Group on Polymer Gels, The Society of Polymer Science of Japan and co-sponsored by the Science and Technology Agency (ST A) and MIT , Japan. The Symposium took place at Tsukuba Science City on 18th and 19th September, 1989. Recognized experts in their fields were invited to speak and there was a strong attendance from government, academic and industrial research centers. The purpose of the Symposium was to review the state of the art and to present and discuss recent progress in the understanding of the behavioral properties of polymer gels and their application to biomedical, environmental and robotic fields. Most of the papers and related discussions concentrated on the swelling behavior of hydrogels and chemomechanical systems, both artificial and naturally occurring, in which external stimuli of a physical or chemical nature control energy transformation or signal transduction. The recent great interest in chemomechanical systems based on polymer gels has stimulated considerable effort towards the development of new sensors and actuators, controllable membrane separation processes, and delivery systems in which the functions of sensing, processing and actuation are all built into the polymeric network device. Artificial chemomechanical systems, through the use of environmentally sensitive polymer gels, are emerging as interesting materials for mimicking basic processes previously only confined to the biological world, and commercially viable applications are also foreseen in the not-too-distant future

The activation of carbon dioxide by transition metal complexes has been extensively studied. both experimentally and theoretically. 1 Central reactions in this chemistry are the insertion of C02 into M-X bonds. where X = H. C. 0. and N. (eq. 1-4). We are presently investigating the mechanistic aspects of these reaction processes and will herein deSCribe our current level of understanding. Comparisons of the pathway of the carbon-carbon bond fonning process in transition metal chemistry with the well known analogous chemistry involving organolithium reagents will be presented. Furthermore. the role of these reaction types in both homogeneous and heterogenous catalytic processes leading to useful chemicals will be elaborated. _OM> (1) lMt-H + ~ lMlopi _OM> (2) [Mt-R + C0. 2 [M]0. 2CR _OM> (3) [Mt-OR+ ~ [M]0. 2COR _OM> (4) [Mt-NR2 + C0. 2 [M]~CNR2 Insertion of C02 into the Metal-Hydride Bond. The reaction of anionic group 6 (Cr. Mo. W) transition metal hydrides with carbon dioxide to afford metalloformates occurs readlly at ambient temperature and 2 reduced pressures of carbon dioxide. This insertion process is referred to the normal pathway (Scheme 1). There are no documented cases of C02 insertion into the metal hydride bond to provide the alternative. metallocarboxylic acid. isomer (referred in Scheme 1 as abnormal). 3 Recent theoretical studies ascribe this preference to an unfavorable electrostatic interaction and poorer orbital overlap in the latter pro 4 cess. Nevertheless.

Explanation of the structure-property relationship of a given molecule is generally simple because the characteristics of the atomic groups and chemical bonds and the effects emerging from their interaction have long been known, both from theore- cal studies and numerous experimental results. In contrast, it is often difficult to analyze, estimate, and account for the structure-properties relationship in sup- molecules. The characteristics of supramolecules are governed both by the nature of the constituent molecules and by their configuration while the characteristics of the constituent molecules are usually evident as mentioned above; their configu- tions are difficult to control, predict, and accurately estimate because of insufficient knowledge regarding the intermolecular forces. Moreover, since most of the int- molecular forces constructing supramolecules are weak, the supramolecular str- ture may vary depending on various factors, such as modification of the molecular structure, auxiliaries, and experimental conditions. Thus, in order to obtain supramolecules with the desired structures and properties, theoretical investigations on the intermolecular forces and accumulation of experimental studies on the re- tionship between the supramolecular structure and properties are both important.

Since the discovery of high temperature superconductivity, a tidal wave of res earch into the newly found phenomena took off in several directions. The theor ists began to examine BSC and its implications. Mostly everyone was syn thesizing materials.The experimentalists were studying relations among electri cal and magnetic properties while the pure materials scientists began to exam ine the microstructures, and the relations of processing to one or two measurab le parameters. The engineering and systems community were preparing real conductors and designing the needed components. Each of the communities was holding between two and three annual meetings to discuss most recent re sults. As work progressed, and promised applications did not materialize, it became apparent to us that the physics and materials science communities needed to establish solid communication lines. This NATO Advanced Study Institute was thus conceived and organized. This was a two week summer school, which 15 internationally acclaimed physicists and material scientists were invited to par ticipate in the capacity of Lecturers. Eighty students, from 12 different countries, also attended."