Metal Metal Bonds And Clusters In Chemistry And Catalysis

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.

Transition metal carbonyl clusters (TMCCs) continue to inspire great interest in chemical research, as much for their fascinating structures as for potential industrial applications conferred by their unique properties. This highly accessible book introduces the bonding, structure, spectroscopic properties, and characterization of clusters, and then explores their synthesis, reactivity, reaction mechanisms and use in organic synthesis and catalysis. Transition Metal Carbonyl Cluster Chemistry describes models and rules that correlate cluster structure with electron count, which are then applied in worked examples. Subsequent chapters explain how bonding relates to molecular structure, demonstrate the use of spectroscopic techniques such as NMR, IR and MS in cluster chemistry, and outline the factors contributing to the stability, dynamics and reactivity of clusters. The second part of this book discusses the synthesis and applications of TMCCs. It emphasizes the differences between the reactivities of clusters vs. mononuclear metal complexes, contingent to the availability of multiple-bonding sites and heterosite reactivity. The final chapters discuss reactions in which clusters act as homogeneous catalysts; including discussion on the use of solid and biphasic liquid-liquid supported clusters in heterogeneous catalysts. A useful reference for those commencing further research or post-graduate study on metal carbonyl clusters and advanced organometallic chemistry, this book is also a cornerstone addition to academic and libraries as well as private collections.

Metal cluster chemistry is at the cutting edge between molecular and solid-state chemistry and has therefore had a great impact on the researchers working on organic, coordination, and solid-state chemistry, catalysis, physics, and materials science. The development of new sophisticated synthetic techniques has led to enormous progress in the synthesis of this diverse class of compounds. The number of clusters is growing rapidly, since the possible variations in the metal and ligand sphere are numerous. Modern bonding theories, such as the isolobal principle, have allowed a better understanding of the structures and properties of metal clusters, and thus paved the way for the usage of these versatile materials. Catalysis and nanomaterials are just two of the very promising application-oriented fields. Seventy six contributions, written by world experts in this research field, provide extensive coverage of different aspects of cluster chemistry, ranging from synthesis, structure determination, and dynamics to applications. Up-to-date information, including an impressive collection of structural data and illustrations, extensive coverage of the most important publications of the last decade, and many more features make this three-volume set a complete single-source guide for all researchers working in the area of cluster chemistry.

Research on metal clusters (compounds with metal-metal bonds) has undergone explosive growth and the subject is now perhaps one of the hottest'' topics in organometallic chemistry. The prospect of catalytic applications has motivated a large part of the research mentioned in this book - the long term goal being to exploit the unique properties of metal clusters to prepare catalysts with new activities and selectivities. This is the first book to address the role of metal clusters in catalysis. The coverage is up-to-date and is particularly comprehensive, ranging from molecular chemistry of clusters (synthesis, structure, thermochemistry, reactivity, and homogeneous catalysis) to supported clusters (molecular analogues on polymers, and metal oxides and metals in zeolite cages). Preparation by methods of organometallic surface chemistry and metal atom chemistry and characterization of surface structures by physical methods are highlighted. Concepts unifying metal cluster chemistry and the chemistry of metal surfaces are elucidated. Of particular value to the user will be the cluster and subject indexes. The cluster index is organized in alphabetical order according to the metal.

Seven chapters summarize the current status of organometallic cluster chemistry from the viewpoints of synthesis, structure and bonding, ligand substitution reactions, ligand transformations, polyhedral rearrangement, cluster fragmentation reactions, and metal clusters as homogeneous catalysts. An eighth provides an extensive bibliography of reviews for the period from 1965 to 1988. Annotation copyrighted by Book News, Inc., Portland, OR

This book discusses current techniques and instrumentation for cluster chemistry. It addresses both the experimental and theoretical aspects of gas-phase metal cluster reactivities, especially those pertaining to pollution removal, energetic reactions and corrosion and anticorrosion. These metal cluster systems have attracted enormous interest as they display a completely new class of physical, chemical, electronic, magnetic and catalytic properties. As these properties change with size and composition, it can thus be understood how their nature evolves from atoms to bulk solids. The book offers readers a basic understanding of the structural chemistry and reactivity of metal clusters in both gas-phase and wet chemistry. Further, the lessons they learn here regarding metal cluster chemistry will prepare researchers for the study of condensed phase dynamics that pertain to wet chemical synthesis, soft-landing deposition and cluster assembly.

Cluster chemistry is one of the recent, exciting areas of Inorganic Chemistry. The occurence of molecular clusters, like fullerene C60, constitutes a fundamental feature midway between the chemistry of isolated chemical compounds and that of the elements. Main features of the Cluster Chemistry of both main group and transition metal elements are treated in this book. The author highlights aspects releated to the synthesis, the structure, the special bonding and the reactivity of these species. The book is written as a textbook for senior undergraduate and postgraduate students. References in tables andillustrations permit the reader to reach relevant original information. Professor Gonzalez-Moraga fills a demand for a publication appropriate for dissemination and specially for teaching this exciting subject. From the Contents: Current Concepts in Modern Chemistry - Transition Metal Cluster Chemistry - Main Group-Transition Metal Mixed Clusters - Cluster Compounds of the Main Group Elements - Synthetic Analogues of the Active Sites of Iron-Sulfur Proteins.