An Introduction to Coordination Chemistry

As noted in Chapter 1, one of the most productive areas of research in the twentieth century was Alfred Werner s development of coordination chemistry. It is a measure of Werner s impact on the realm of inorganic chemistry that the number, variety, and complexity of coordination compounds continue to grow even as we pass the centennial anniversary of his original work. Before we launch into a historical perspective on the development of this vital subsection of inorganic chemistry, we need to set the stage with a few important definitions. 

Coordination chemistry concerns compounds in which a small number of molecules or ions called ligands surround a central metal atom or ion. Each ligand (from the Latin ligare, meaning to bind ) shares a pair of its electrons with the metal. The metal ligand bond, often represented as M ----- L, is an example of a coordinate-covalent 

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Graddon, D. P., An Introduction to Coordination Chemistry, Pergamon, London, 1961. 

S. For a review of this subject, see almost any modern text on inorganic chemistry or coordination chemistry. A particularly attractive account is contained in Orgel, L. E., An Introduction to Transition Metal Chemistry, Wiley, New York, 1962. 

The material presented in this chapter provides an introduction to the vast area of reactions of coordination compounds. In addition to the types of reactions described, there is an extensive chemistry of reactions of coordinated ligands. Because many ligands are organic molecules, it is possible to carry out reactions on the ligands without disruption of the complexes, and some such reactions have been mentioned in this chapter. Several others will be shown in Chapter 21. Many reactions of coordination compounds have been studied in detail, and much is known about processes taking place in both solids and solutions. However, it is not possible in a book such as this to do more than introduce the field, but the listed references provide a basis for further study of this area. 

Organic chemistry is an experimental science it was developed by coordination of reasoning and experiment. The best way to obtain an introduction to this field of knowledge is a well-directed study involving a certain amount of laboratory practice. It is desirable to acquaint the student at the very beginning with the purpose of laboratory work. From the instructor s point of view the chief aims of laboratory practice in the study of elementary organic chemistry are ... 

Schwarz, Robert, Lawrence W. Bass, and Alfred Werner. The Chemistry of the Inorganic Complex Compounds An Introduction to Werner s Coordination Theory. New York Wiley, 1923. 

The importance of Marcus theoretical work on electron transfer reactions was recognized with a Nobel Prize in Chemistry in 1992, and its historical development is outlined in his Nobel Lecture.3 The aspects of his theoretical work most widely used by experimentalists concern outer-sphere electron transfer reactions. These are characterized by weak electronic interactions between electron donors and acceptors along the reaction coordinate and are distinct from inner-sphere electron transfer processes that proceed through the formation of chemical bonds between reacting species. Marcus theoretical work includes intermolecular (often bimolecular) reactions, intramolecular electron transfer, and heterogeneous (electrode) reactions. The background and models presented here are intended to serve as an introduction to bimolecular processes. 

For an introduction to the use of [Ni(Hdmg)2] and related complexes in template syntheses of macrocycles, see E.C. Constable (1999) Coordination Chemistry of Macrocyclic Compounds, Oxford University Press, Oxford (Chapter 4). 

For a detailed review, see A. Juris, V. Balzani, F. Barigelletti, S. Campagna, P. Belser and A. von Zelewsky (1988) Coordination Chemistry Reviews, vol. 84, p. 85 - Ru(II) polypyridine complexes Photophysics, photochemistry, electrochemistry and chemiluminescence . For an introduction to photochemical principles, see C.E. Wayne and R.P. Wayne (1996) Photochemistry, Oxford University Press Primer Series, Oxford. 

The following description summarizes the knowledge on ferritins which has been reviewed since the early 1970s and is designed to provide an introduction to the more detailed discussion on the coordination chemistry aspects which appears in Section 8.7.4. 

The mechanisms of surface chemical reactions represent a problem in coordination chemistry, which is the study of complexes, molecular units comprising a central group surrounded by other atoms in close association. This book is principally an introduction to the interpretation of surface phenomena in soils from the point of view of coordination chemistry. Therefore the basic concept to be discussed is the surface functional group, the central moiety in surface complexes, whose formation provides the most important mechanism of adsorption by the solid phases in soils. No detailed consideration of adsorption isotherm equations or the thermodynamic theory of ion exchange is presented, except insofar as their tenuous relation with surface coordination chemistry is to be illustrated. The discussion in this book is intended to be self-contained, but a previous exposure to soil physical chemistry, soil mineralogy, and the fundamentals of inorganic chemistry will prove helpful. 

Orgel, L. E. International Conference on Coordination Chemistry London Chemical Society London, 1959 p 93 An Introduction to Transition Metal Chemistry Ugand-Field Theory Methuen London, 1960, p 132. 

G.J. Uong and F. Grandjean (2004) in Comprehensive Coordination Chemistry II, eds J.A. McCleverty and T.J. Meyer, Elsevier, Oxford, vol. 2, p. 269 - An introduction to Mossbauer spectroscopy with references to pertinent literature examples. 

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