Metal Clusters In Chemistry

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.

On Friday, February 20, 1980, I had the pleasure to be present at the inaugural lecture of my colleague Jan Reedijk, who had just been named at the Chair of Inorganic Chemistry of Leiden University. According to tradition, the ceremony took place in the impressive Hall of the old University Academy Building. In the course of his lecture, Jan mentioned a number of recent developments in chemistry which had struck him as particularly important or interesting. Among those was the synthesis of large metal cluster compounds, and, to my luck, he showed a slide ofthe molecular structure of [PtI9(C)b]4-. (To my luck, since at traditional Leiden University it is quite unusual to show slides at such ceremonies.) This constituted my first acquaintance with this exciting new class of materials. I became immediately fascinated by this molecule, partly because of the esthetic beauty of its fivefold symmetry, partly because as a physicist it struck me that it could be visualized as an "embryonically small" metal particle, embedded in a shell of CO ligands.

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.

Numerous experiments and calculations have shown that isolated metal clusters possess many interesting features, quite different from those known from surface and solid- state physics or from atomic and molecular physics. The technological exploitation of these new properties, e.g. in miniature electronic or mechanical components, requires the cluster to be brought into an environment such as an encapsulating matrix or a surface. Due to the interaction with the contact medium, the properties of the clusters may change or even disappear. Thus the physics of cluster-on-surface systems -- the main subject of this book -- is of fundamental importance. The book addresses a wide audience, from the newcomer to the expert. Starting from fundamental concepts of adsorbate-surface interactions, the modification of electronic properties through electron confinement, and concepts of cluster production, it elucidates the distinct properties of the new metallic nanostructures.

Protected Metal Clusters: From Fundamentals to Applications surveys the fundamental concepts and potential applications of atomically precise metal clusters protected by organic ligands. As this class of materials is now emerging as a result of breakthroughs in synthesis and characterization that have taken place over the last few years, the book provides the first reference with a focus on these exciting novel nanomaterials, explaining their formation, and how, and why, they play an important role in the future of molecular electronics, catalysis, sensing, biological imaging, and medical diagnosis and therapy. Surveys the fundamental concepts and potential applications of atomically precise metal clusters protected by organic ligands. Provides well-organized, tutorial style chapters that are ideal for teaching and self-study In-depth descriptions by top scientists in the field Presents the state-of-the art of protected metal clusters and their future prospects

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

An advanced-level textbook of inorganic chemistry for the graduate (B.Sc) and postgraduate (M.Sc) students of Indian and foreign universities. This book is a part of four volume series, entitled "A Textbook of Inorganic Chemistry – Volume I, II, III, IV". CONTENTS: Chapter 1. Stereochemistry and Bonding in Main Group Compounds: VSEPR theory, dπ -pπ bonds, Bent rule and energetic of hybridization. Chapter 2. Metal-Ligand Equilibria in Solution: Stepwise and overall formation constants and their interactions, Trends in stepwise constants, Factors affecting stability of metal complexes with reference to the nature of metal ion and ligand, Chelate effect and its thermodynamic origin, Determination of binary formation constants by pH-metry and spectrophotometry. Chapter 3. Reaction Mechanism of Transition Metal Complexes – I: Inert and labile complexes, Mechanisms for ligand replacement reactions, Formation of complexes from aquo ions, Ligand displacement reactions in octahedral complexes- acid hydrolysis, Base hydrolysis, Racemization of tris chelate complexes, Electrophilic attack on ligands. Chapter 4. Reaction Mechanism of Transition Metal Complexes – II: Mechanism of ligand displacement reactions in square planar complexes, The trans effect, Theories of trans effect, Mechanism of electron transfer reactions – types; Outer sphere electron transfer mechanism and inner sphere electron transfer mechanism, Electron exchange. Chapter 5. Isopoly and Heteropoly Acids and Salts: Isopoly and Heteropoly acids and salts of Mo and W: structures of isopoly and heteropoly anions. Chapter 6. Crystal Structures: Structures of some binary and ternary compounds such as fluorite, antifluorite, rutile, antirutile, crystobalite, layer lattices- CdI2, BiI3; ReO3, Mn2O3, corundum, pervoskite, Ilmenite and Calcite. Chapter 7. Metal-Ligand Bonding: Limitation of crystal field theory, Molecular orbital theory, octahedral, tetrahedral or square planar complexes, π-bonding and molecular orbital theory. Chapter 8. Electronic Spectra of Transition Metal Complexes: Spectroscopic ground states, Correlation and spin-orbit coupling in free ions for Ist series of transition metals, Orgel and Tanabe-Sugano diagrams for transition metal complexes (d1 – d9 states), Calculation of Dq, B and β parameters, Effect of distortion on the d-orbital energy levels, Structural evidence from electronic spectrum, John-Tellar effect, Spectrochemical and nephalauxetic series, Charge transfer spectra, Electronic spectra of molecular addition compounds. Chapter 9. Magantic Properties of Transition Metal Complexes: Elementary theory of magneto - chemistry, Guoy’s method for determination of magnetic susceptibility, Calculation of magnetic moments, Magnetic properties of free ions, Orbital contribution, effect of ligand-field, Application of magneto-chemistry in structure determination, Magnetic exchange coupling and spin state cross over. Chapter 10. Metal Clusters: Structure and bonding in higher boranes, Wade’s rules, Carboranes, Metal Carbonyl Clusters - Low Nuclearity Carbonyl Clusters, Total Electron Count (TEC). Chapter 11. Metal-π Complexes: Metal carbonyls, structure and bonding, Vibrational spectra of metal carbonyls for bonding and structure elucidation, Important reactions of metal carbonyls; Preparation, bonding, structure and important reactions of transition metal nitrosyl, dinitrogen and dioxygen complexes; Tertiary phosphine as ligand.

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.

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.