Names of coordination compounds

The names of coordination compounds can become awesomely long because the identity and number of each type of ligand must be included. In most cases, chemists avoid the problem by using the chemical formula rather than the name itself. For instance, it is much easier to refer to [FeCl(H20)5]+ than to pen-taaquachloroiron(II) ion, its formal name. However, names are sometimes needed, and they can be constructed and interpreted, in simple cases at least, by using the rules set out in Toolbox 16.1. Table 16.4 gives the names of common ligands and their abbreviations, which are used in the formulas of complexes. 

Example provides more practice in working with the names of coordination compounds. Our Chemical Milestones Box describes the detective work that led to the birth of coordination chemistry. 

A number of rules have been adopted internationally for the naming of coordination compounds ... 

The naming of coordination compounds is illustrated examples that will illustrate the principles involved. 

The systematic naming, or nomenclature, of coordination compounds can be complicated to apply, but it is essential to have some familiarity with the basic rules of nomenclature and to be able to work out the structure of a compound from its systematic name. Only a very brief summary of the rules for naming of coordination compounds can be given here, but more detailed accounts are available elsewhere. " ... 

This set of rules was based upon a report drawn up by H. Remy (32) on behalf of the German Chemical Society and in collaboration with some of its members of whom A. Stock was the most active. The portion of the rules devoted to coordination compounds amounts to little more than half a page of the Journal of the American Chemical Society. In essence, the rules endorsed the nomenclature practices introduced by Werner with the substitution of Stock numbers to indicate valence in place of the cumbersome vowel suffixes of Werner. The amount of page space devoted to coordination compounds in the rules is no indication of the influence of the rules upon practice in the naming of coordination compounds. In a few years, systematic names had almost completely displaced unsystematic names which had been firmly established. 

The pattern of chemical combination represented by coordination compounds is one of common occurrence. The adoption of a basic plan of nomenclature for this fundamental pattern of chemical combination is desirable. The basic philosophy underlying the various schemes for the naming of coordination compounds is reviewed briefly. The causes of apparent contradictions are discussed. The practices for the nomenclature of coordination compounds suggested by the Commission on the Reform of Inorganic Chemical Nomenclature of the International Union of Chemistry (1940) previously were formulated into a set of rules (1948). These rules are now modified in the light of criticism and further study and are extended to cover situations not previously included. Examples are given to show how the practices prescribed by the rules may be extended. 

In names of coordination compounds, the ligand names precede the name of the central atom and are cited in alphabetical order. For each ligand type, bridging ligands are cited immediately before terminal ligands of the same kind, if any, e.g. di-p-chlorido-... 

In the names of coordination compounds and boron compounds, the punctuation marks used to separate the symbols of atoms from the numerical locants, the locants indicating bridging atoms, and the various other sets of locants which may be present, are arranged in the following hierarchy ... 

Recognition of the relationships between these complex compounds led to the formulation of coordination theory and the naming of coordination compounds using additive nomenclature. Each coordination compound either is, or contains, a coordination entity (or complex) that consists of a central atom to which other groups are bound. 

Examples 15.2 and 15.3 show how to apply these rules to the naming of coordination compounds. 

Formulas and names of coordination compounds follow systematic rules. 

Complex Ions Coordination Numbers, Geometries, and Ligands 744 Formulas and Names of Coordination Compounds 745... 

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