Carbosilanes are compounds in which the elements silicon and carbon alternate in the molecular skeleton [1]. Just as the alkanes are formally derived from the diamond lattice and the aromatics from the graphite lattice, the carbosilanes are structurally derived from silicon carbide. Because of the tetravalent nature of silicon and carbon we can expect stable linear, cyclic and polycyclic compounds to occur. However, carbosilanes do not exist in nature. This book is an attempt to give a summarized presentation. Carbosilanes are, of course, part" of organosilicon chemistry, but their behavior differentiates them distinctly from other organosilicon compounds. The differences result primarily from the alternating Si-C-Si arrangements in the molecular skeleton, and especially the various methylene bridges (CH , CHX, CX ; X = halogen) cause changes in z z Si-C bond polarization and hence influence the reaction possibilities. It is convenient to regard carbosilanes as similar to silicones except that the oxygen bridges of silicones are replaced by methylene units. However, this does not accurately account for all the chemical properties of these compounds. Carbosilanes are related more directly to silicon carbide, as shown occasionally by the reactive behavior of polycyclic car bosilanes. Therefore, in view of the present interest shown for thermally stable cera mics of unusual character, interesting possibilities arise for further development. Most cyclic carbosilanes can be classified in two groups: the carborundanes and the Si-scaphanes. Compounds belonging to the carborundane class maintain Si-C six-membered rings in the boat conformation.

Cluster science studies the transition from atomic, and molecular physics or chemistry to the science and technology of condensed matter. Two main topics from this large field will be emphasized in this second volume of Atomic and Molecular Clusters. After an Introduction, Chap. 2 deals mainly with molecular clusters, how they react to positive or negative charges (Sect. 2.1 to 2.5), how they decompose and how they can be charged (Sect. 2.6 and 2.7), and how one can do chemistry with them (2.8 and 2.9). Clusters in contact with a macroscopic medium are treated in Chap. 3. It is from this domain that one can expect possible new applications of cluster science. The optical spectra of silver clusters in a dielectric medium are discussed in Sect. 3.1. Their properties have since long been used unknowingly to stain glass windows. Large clusters floating in an ambient pressure gas are called aerosols (Sect. 3.2). Their properties can be used to monitor air pollution. Development of a photographic film is due to supported silver clusters in a liquid environment (Sect. 3.3). Large semiconductor clusters, also called "quantum dots," have novel optical and electronic properties (Sect. 3.4). The optical properties of large clusters, in general, are reviewed in Sect. 3.5, and properties of clusters supported on clean surfaces are discussed in Sect. 3.6.

The literature in polymerization reaction engineering has bloomed sufficiently in the last several years to justify our attempt in putting together this book. Rather than offer a comprehensive treatment of the entire field, thereby duplicating earlier texts as well as some ongoing bookwriting efforts, we decided to narrow down our aim to step growth polymerization systems. This not only provides us the lUxury of a more elaborate presentation within the constraints of production costs, but also enables us to remain on somewhat familiar terrain. The style and format we have selected are those of a textbook. The first six chapters present the principles of step growth polymerization. These are quite general, and can easily be applied in such diverse and emerging fields as polymerization applications in photolithography and microelec tronics. A detailed discussion of several important step growth polymeriz ations follows in the next five chapters. One could cover the first six chapters of this book in about six to eight weeks of a three-credit graduate course on polymerization reactors, with the other chapters assigned for reading. This could be followed by a discussion of chain-growth and other polymeriz ations, with which our material blends well. Alternately, the entire contents of this book could be covered in a course on step growth systems alone."

Remarks by JVS. Volumes 1 and 2 of Feldspar Minerals were published in 1974, but Volume 3 was not completed because I was forced to devote 3 years to the resolution of unforeseen problems in the construction of an ion probe. By 1977, the incomplete draft for Volume 3 had become obsolete because of the enormous advances in knowledge of feldspars, particularly those in lunar rocks and meteorites, and in both deep-seated and ancient terrestrial rocks. Furthermore, it soon became obvious that a completely new version of Feldspar Minerals was needed because of the important new results on the physical and chemical properties. I had kept up with the interesting but tedious chore of weekly reading of the incoming literature and maintenance of the files. By 1980, the intense day-to day pressure had gone from my research programs on lunar rocks and on the development of the ion microprobe as a quantitative geochemical instrument, and I began preparation of a second edition of Feldspar Minerals."

The effects of heat and light on chemical reactions have long been known and un derstood. Ultrasound has been known to promote chemical reactions for the past 60 years, but despite this, it did not attract the attention of synthetic chemists until recently. This arose historically from early studies which concentrated almost exclu sively on reactions in aqueous media and was also, in some measure, due to the availability of suitable technology. Since the early 1980s a plethora of literature has appeared of direct interest to synthetic chemists and the field has been developing rapidly. The aim of this book is to bring the background of this fascinating field to the atten tion of a wider audience. It explores the literature to date and attempts to indicate other areas in which ultrasound may be exploited. It also hopes to explode some of the myths surrounding this area which have hitherto been regarded by the synthetic community as a bit of a black art! Existing books and reviews have tended to concentrate on the physics of sonochem istry and to catalogue the instances in which ultrasound has proved useful in tack ling synthetic problems. Our aim has been to stress the relevance of this technique to synthetic chemists and we have included a section which deals with the practical aspects of carrying out these reactions.

"Highly recommended for all academic library chemistry collections; biochemistry and medical collections may also want to consider." (Choice)
"Each entry is provided with a definition, a description of the effect, application, and literature citations...". the selection in this book is broad and useful." (J. of Am. Chem. Soc.)
"The book is not just a collection of definitions of acronyms, each entry contains a concise and informative explanation of the origins of the technique or method to which it refers... this book is a must for progression of any budding spectroscopist." (Analyst)

There are only few topics in organometallic chemistry, which have stimulated research activities in as many areas, as transition-metal carbene (alkylidene) complexes. About 25 years after the first planned synthesis of a carbene complex in E.O. Fischer's laboratory in Munich the NATO Advanced Research Workshop on Transition-Metal Carbene Complexes was the first meeting which, brought together scientists from different disciplines to discuss inorganic, organic, theoretical structural catalysis-related aspects of metal carbene chemistry. The 70th birthday of Professor E.O. Fischer was a good occasion for this enterprise. The organizers of the meeting (K.D. Dotz, Marburg; F.R. KreiBl, Munchen; U. Schubert, Wurzburg) were encouraged by the fact that most of the leading scientists in this area were able to participate in the workshop. The very high standard of the contributions is reflected in this book, which contains papers from the majority of the participants. The Proceedings show the state of the art in metal carbene chemistry and will hopefully be a landmark in the development of this area of chemistry. Generous financial support for the workshop and for the preparation of this book was provided by the Scientific Affairs Division of NATO and some companies. The organizers also acknowledge the efforts of the staff of the Bildungs zentrum der Hans-Seidel-Stiftung in Wild bad Kreuth for creating a pleasant and stimulating atmosphere during the conference."

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."

This issue of Zeitschrift fUr Physik D contains papers which were presented at the 5th International Symposium on Small Particles and Inorganic Clusters. ISSPIC5 was held at the University of Konstanz, Germany, from September 10 to 14, 1990. There were 33 invited talks, and 295 papers were contributed. 14 particularly interesting papers had been selected by the International Advisory Board: they were presented during one of the regular sessions. In addition, two last-minute contributions, describing break throughs in the synthesis and characterization of size-selected fullerene carbon clusters, were communicated orally. The other contributions were presented during two poster sessions, comprising nearly twice as many papers as during the previous symposium in Aix-en-Provence, in 1988. Approximately 250 manuscripts were received, and all were refereed during the sympo sium. Several of them had to be revised, but only a small number were rejected. The contributions in this volume are grouped according to the topic, roughly following the scheme adopted during the conference."

Despite the recent progress in developing various microanalytical tools of better spatial resolution and more sensitivity to chemical analyses for the study of various defects in metallic solids the Field-Ion Microscope (FIM) still remains the only instrument up to now to resolve single atoms in the surface of a metal. Fifteen years after Milller ) invented the FIM he was also the first to combine the FIM with a time-of-flight (ToF) mass spectrometer - the so-called Atom-Probe FlM - to identify the chemical nature of single atoms imaged in the FIM2). Originally the motivation to develop the ToF atom probe was to use this method to obtain some more fundamental understanding of field ionization and field evaporation, the most basic physical processes in field-ion microscopy. Even after the successful combination of a FIM with a ToF atom probe had been accomplished, the technique was rarely applied to metallurgical investigations since for a fairly long period only refractory metals such as tungsten, molybdenum, iridium, etc. could be imaged in the FIM. How ever, these metals do not playa very important role in metallurgy. Only when Turner et 3 al. ) substituted the conventional phosphorescent screen of the field-ion microscope with micro-channel electron multiplier arrays, termed micro channel plates, did it become possible to image in the FIM the less refractory metals like Fe, Cu, Ni and even AI."

In solid state physics and in materials science the investigation of the connection between the properties of solids and their microstructure is of major importance. For crystalline materials this connection is related to the lattice structure, and it can be shown convinc ingly that the material properties depend on deviations from the ideal lattice structure in the majority of cases. For this reason a reliable detection and analysis of defects in "nearly perfect" crystals is necessary, and a sufficient spatial resolution of the methods applied is required. Because electrons on the one hand strongly interact with the matter to be investigated and on the other hand can easily be focused electron-optical methods are very advantageous for this purpose. They are used in the diffraction mode, in the imaging mode and in the spectroscopic mode. The attainable high lateral resolution in the imaging mode makes the application of electron microscopy especially effective. Although already valuable information on crystal defects can be gained by using the routine technique of diffraction contrast imagingl-3) which has a resolution of some 4 10 nm - in the special weak-beam technique ) of some nm -, the detection of crystal defects and inhomogeneities, resp. on an atomic or molecular level by the aid of high resolution electron microscopy gets increasing importance."

During the oil embargo, in the winter 1973174, parts of Western Europe present ed an almost war-like aspect on Saturdays and Sundays: no traffic on the high ways, no crowds at ski resorts and other weekend entertainment places, no gaso line at the pumps. Living and teaching then in that part of the world, and discussing the situa tion with our students, we came to the conclusion that it would be timely to col lect the fine chemistry already known at the time in the field of conversion of coal to gasoline and other chemicals, and by this way help to draw the attention to this important alternative to crude oil. The idea of this book was born. The energy shock of the early seventies has been healthy and of great conse quences in chemistry. Large amounts of research money have been put to work since, and our knowledge of the possibilities and limitations of coal-based chemistry has increased enormously. During several years it appeared inap propriate to write a monograph about a topic which was in the midst of such an impetuous development. Nevertheless, we collected, and critically selected, the upcoming work as it appeared in the literature, and also tried to provide some modest input ourselves. Now, ten years later, the situation seems to be settled to a certain degree."

This book contains the proceedings of the international workshop on Many-Atom Interactions in Solids, which was held June 5-9, 1989, in Pajulahti, Finland. The purpose of the workshop was to bring together physicists, chemists and materials scientists working in the field of interatomic interactions and their applications in computer simulations of condensed matter. The workshop attracted a good fraction of the active groups in the field, and created lively discussion and interchange of ideas. The contributions in this volume have been grouped by the editors into review type articles and more specific applications to different topics. The order of the articles does not follow the order of the presentations in the workshop. The editors wish to express their gratitude first of all to all the workshop par ticipants for creating an enjoyable and fruitful workshop and to the contributors for their efforts in putting together these proceedings. We hope that this volume will be a useful resource for practitioners in and newcomers to this exciting field. We would like to thank Jens N!l1rskov for his help in planning the scientific pro gramme and Eija Jarvinen for taking care of most of the practical arrangements of the workshop. The workshop was made possible by financial support from the Finnish Ministry of Education, the Research Institute for Theoretical Physics (Helsinki), NORDITA (Copenhagen), and Helsinki University of Technology.

Considering aspects of symmetry rules in chemistry, one is faced with con tradictory terms as for example, "90 % concertedness" sometimes being used in literature. To accept conservation of orbital symmetry to be as controlled as inversion by alternative principles seems far more promising. The intention of this book is aimed at introducing a qualitative understanding of phase rela tions in electromagnetic interactions. Avoiding one-sided dogmatism we tried to demonstrate the importance of alternative principles as guidelines to the evolution of alternative order in chemical systems. Passing through the jungle of information it became extremly important to control again and again our insights into the ordering phenomena by experi ments under conditions as coherent as possible. We became more aware of the fact that chemistry - the science of "becoming" in complex systems - can not be understood by mechanistic details, i. e. THROUGHPUT-studies alone, because the mechanism is only true for the special system under inves tigation and does not offer a tool for the evolution of opposite order. We had to accept chemistry as a mediator between molecular physics and general epistemology. This quite unusual combination was directed by excel lent teachers and the realizations were made possible by enthusiastic, open minded coworkers (see references). The next target we will strive for on this journey will be to quantify the alternative principles, that means obtaining the order parameters of H. Haken (e. g. in asymmetric synthesis).

''A must for anyone interested in metal-containing polymers and all its aspects.'' ---American Scientist ''Nicely organized...well-written....An excellent shapshot of the current state of this field.'' ---MRS Bulletin, July 1998

EJB Reviews 1989 offer the collection of all reviews published in the European Journal of Biochemistry in one handy volume. This series of review articles by leading scientists covers emerging and rapidly growing fields of research in fundamental as well as in applied areas of biochemistry, such as medicine, biotechnology, agriculture and nutrition. Novel methodological and technological approaches which stimulate biochemical research are also included. All authors review their field in a very critical, selective, evaluative manner, with emphasis on interdisciplinary aspects wherever possible.

In the first contribution to this volume we read that the world-wide production of single crystal silicon amounts to some 2000 metric tons per year. Given the size of present-day silicon-crystals, this number is equivalent to 100000 silicon-crystals grown every year by either the Czochralski (80%) or the floating-zone (20%) technique. But, to the best of my knowledge, no coherent and comprehensive article has been written that deals with "the art and science," as well as the practical and technical aspects of growing silicon crystals by the Czochralski technique. The same could be said about the floating-zone technique were it not for the review article by W. Dietze, W. Keller and A. Miihlbauer which was published in the preceding Volume 5 ("Silicon") of this series (and for a monograph by two of the above authors published about the same time). As editor of this volume I am very glad to have succeeded in persuading two scien tists, W. Zulehner and D. Huber, of Wacker-Chemitronic GmbH - the world's largest producer of silicon-crystals - to write a comprehensive article about the practical and scientific aspects of growing silicon-crystals by the Czochralski method and about silicon wafer manufacture. I am sure that many scientists or engineers who work with silicon crystals -be it in the laboratory or in a production environment - will profit from the first article in this volume."

The recent discovery of high-temperature superconductivity in copper based oxides is an event of major importance not only with respect to the physical phenomenon itself but also because it definitely shows that solid state chemistry, and especially the crystal chemistry of oxides, has a crucial place in the synthesis and understanding of new materials for future appli cations. The numerous papers published in the field of high Tc supercon ductors in the last five years demonstrate that the great complexity of these materials necessitates a close collaboration between physicists and solid state chemists. This book is based to a large extent on our experience of the crystal chemistry of copper oxides, which we have been studying in the laboratory for more than twelve years, but it also summarizes the main results which have been obtained for these compounds in the last five years relating to their spectacular superconducting properties. We have focused on the struc ture, chemical bonding and nonstoichiometry of these materials, bearing in mind that redox reactions are the key to the optimization of their supercon ducting properties, owing to the importance of the mixed valence of copper and its Jahn-Teller effect. We have also drawn on studies of extended defects by high-resolution electron microscopy and on their creation by ir radiation effects."

The intensification of the production of silicate materials and products makes a de tailed theoretical study of the processes underlying their manufacture and service more and more urgent. The thermodynamic method is of great importance for studying chemical reac tions of silicate technology. Together with a study of the rate and mechanism of sub stance transfer, it permits obtaining necessary data for the efficient operation of technological processes. The progress of science in recent years has solved numerous problems in the field of the physical chemistry of silicates. The great progress in deciphering silicate structures, and working out methods of the synthesis of minerals and studying their properties must be mentioned. New methods of determining thermic constants have appeared. In future these methods should be more widely used for determining the heats of the silicate forma tion and related compounds in crystalline and vitreous state. This concerns in par ticular the system - CaO - Ab03 - Fe203 - Si0 - H 0 -which is of great impor 2 2 tance for the technology of cement and concrete, ceramics, refractories and glass."

Within the last few years, iron research has yielded exciting new insights into the under standing of normal iron homeostasis. However, normal iron physiology offers little protec tion from the toxic effects of pathological iron accumulation, because nature did not equip us with effective mechanisms of iron excretion. Excess iron may be effectively removed by phlebotomy in hereditary hemochromatosis, but this method cannot be applied to chronic anemias associated with iron overload. In these diseases, iron chelating therapy is the only method available for preventing early death caused mainly by myocardial and hepatic iron toxicity. Iron chelating therapy has changed the quality of life and life expectancy of thalassemic patients. However, the high cost and rigorous requirements of deferoxamine therapy, and the significant toxicity of deferiprone underline the need for the continued development of new and improved orally effective iron chelators. Such development, and the evolution of improved strategies of iron chelating therapy require better understanding of the pathophysiology of iron toxicity and the mechanism of action of iron chelating drugs. The timeliness of the present volume is underlined by several significant develop ments in recent years. New insights have been gained into the molecular basis of aberrant iron handling in hereditary disorders and the pathophysiology of iron overload (Chapters 1-5)."

In common with the editor of the first edition, my own personal involvement with tin chemistry began when I had the privilege of studying for a PhD degree under the supervision of Professor Alwyn G. Davies FRS at University College London (UCL) almost exactly 30 years ago. Then, following 21 years' service with the International Tin Research Institute, it was a great pleasure for me when the wheel turned full circle and, in 1994, Alwyn - now an Emeritus Professor - asked me to return to UCL as an Honorary Research Fellow in the Chemistry Department. One of my first tasks was when I received an invitation from Blackie A&P to edit the second edition of the Chemistry of Tin, which I was delighted to accept, since it enabled me to continued my life-long interest in tin chemistry and to maintain contact with my former friends and colleagues, many of whom have contributed to this book.

For several years, the two parallel worlds of Molecular Conductors in one hand and Molecular Magnetism in the other have grown side by side, the former essentially based on radical organic molecules, the latter essentially based on the high spin properties of metal complexes. Over the last few years however, organometallic derivatives have started to play an increasingly important role in both worlds, and have in many ways contributed to open several passages between these two worlds. This volume recognizes this important emerging evolution of both research areas. It is not intended to give a comprehensive view of all possible organometallic materials, and polymers for example were not considered here. Rather we present a selection of the most recent research topics where organometallic derivatives were shown to play a crucial role in the setting of conducting and/or magnetic properties in crystalline materials. First, the role of organometallic anions in tet- thiafulvalenium-based molecular conductors is highlighted by Schlueter, while Kubo and Kato describe very recent ortho-metalated chelating ligands appended to the TTF core and their conducting salts. The combination of conducting and magnetic properties and the search for p-d interactions are analyzed in two comp- mentary contributions by Myazaki and Ouahab, while Valade focuses on the only class of metal bis(dithiolene) complexes to give rise to superconductive molecular materials, in association with organic as well as organometallic cations.

Science and art of crystal growth represent an interdisciplinary activity based on fundamental principles of physics, chemistry and crystallography. Crystal growth has contributed over the years essentially to a widening of knowledge in its basic disciplines and has penetrated practically into all fields of experimental natural sciences. It has acted, more over, in a steadily increasing manner as a link between science and technology as can be seen best, for example, from the achievements in modern microelectronics. The aim of the course "Crystal Growth in Science and Technology" being to stress the interdisciplinary character of the subject, selected fundamental principles are reviewed in the following contributions and cross links between basic and applied aspects are illustrated. It is a very well-known fact that the intensive development of crystal growth has led to a progressive narrowing of interests in highly specialized directions which is in particular harmful to young research scientists. The organizers of the course did sincerely hope that the program would help to broaden up the horizon of the participants. It was equally their wish to contribute within the traditional spirit of the school of crystallography in Erice to the promotion of mutual understanding, personal friendship and future collaboration between all those who were present at the school.

Polytypic crystals of semiconductors, dielectrics and magnetic materials attract an increasing attention in science and technology. On one hand, the phenomenon of polyty pism is one of the fundamental problems of solid-state physics; its solution would make it possible to elucidate- the problem of the interconnection of different structures and intraatomic forces acting in crystals. On the other hand, the polytypic difference in crystals is most strongly expressed in electro-physical properties, which makes their application promising, mainly in semiconductor electronics. Thus, the difficulties of pro ducing modulated structures in polytypic crystals can be overcome since these crystals form a class of one-dimensional natural superlattices. At present it has become clear that polytypism in crystals and compounds is the rule rather than an exception and it is determined by the conditions of their synthesis. This phenomenon seems to be rather widespread in nature and fundamental for crystal forma tion. H polytypism was recently thought to be but a specific structural feature of a few substances such as SiC, ZnS, CdI , etc. , by now this phenomenon has been discovered in 2 v an increasing range of crystalline substances, for example, in silicon, diamond, AIIIB , VI AIIB , AIBVII compounds, in ternary semiconducting compounds, metals, silicates, perovskites, mica, organic crystals. The more accurately the structural studies are per formed, the greater is the number of crystals of various substances found to exhibit the phenomenon of polytypism. Recently, excellent surveys have systematized our knowledge of polytypism.

The. first edition of this work appeared almost thirty years ago, when, as we can see in retrospect, the study of the actinide elements was in its first bloom. Although the broad features of the chemistry of the actinide elements were by then quite weil delineated, the treatment of the subject in the first edition was of necessity largely descriptive in nature. A detailed understanding ofthe chemical consequences of the characteristic presence of 5f electrons in most of the members ofthe actinide se ries was still for the future, and many ofthe systematic features ofthe actinide elements were only dimly apprehended. In the past thirty years all this has changed. The application of new spectroscopic techniques, which came into general use during this period, and new theoretical insights, which came from a better understanding of chemical bonding, inorganic chemistry, and solid state phenomena, were among the important factors that led to a great expansion and maturation in actinide element research and a large number of new and important findings. The first edition consisted of aserial description of the individual actinide elements, with a single chapter devoted to the six heaviest elements (lawrencium, the heaviest actinide, was yet to be discovered). Less than 15 % of the text was devoted to a consideration of the systematics of the actinide elements.