27 No. 6
Nomenclature of Inorganic Chemistry*
—IUPAC Recommendations 2005
Prepared for publication by Neil G. Connelly and Ture Damhus (senior editors), and Richard M. Hartshorn and Alan T. Hutton
RSC Publishing, 2005, ISBN 0 85404 438 8
Chemical nomenclature must evolve to reflect the needs of the community that makes use of it. In particular, nomenclature must be created to describe new compounds or classes of compounds, modified to resolve ambiguities that might arise, or clarified where there is confusion over the way in which nomenclature should be used. There is also a need to make nomenclature as systematic and uncomplicated as possible in order to assist less familiar users (for example, because they are only in the process of studying chemistry or are non-chemists who need to deal with chemicals at work or at home). A revision of Nomenclature of Inorganic Chemistry, IUPAC Recommendations 1990 (Red Book I) was therefore initiated in 1998, under the guidance of the IUPAC Commission on Nomenclature of Inorganic Chemistry and then, after the general restructuring of IUPAC, by a project group working under the auspices of the Division VIII: Chemical Nomenclature and Structure Representation.
The need to ensure that inorganic and organic nomenclature systems are, as far as possible, consistent has resulted in extensive cooperation between the editors of the revised Red Book and the editors of Nomenclature of Organic Chemistry (the revised “Blue Book,” in preparation). At present, the concept of preferred IUPAC names (PINs), an important element in the revision of the Blue Book, has not been extended to inorganic nomenclature (though preferred names are used herein for organic, i.e., carbon-containing, compounds when appropriate). A planned future project on inorganic PINs will need to face the problem of choosing between the equally valid nomenclature systems currently in use.
The present book supersedes not only Red Book I but also, where appropriate, Nomenclature of Inorganic Chemistry II (Red Book II). One of the main changes from Red Book I is the different organization of material, adopted to improve clarity. Thus, Chapters IR-5 (Compositional Nomenclature, and Overview of Names of Ions and Radicals), IR-6 (Parent Hydride Names and Substitutive Nomenclature), and IR-7 (Additive Nomenclature) deal with the general characteristics of the three main nomenclature systems applied to inorganic compounds. (Note that the notation ‘IR-’ is used to distinguish chapters and sections in the current book from those in Red Book I, prefixed ‘I-’). The next three chapters deal with their application, particularly that of additive nomenclature, to three large classes of compounds: inorganic acids and derivatives (Chapter IR-8), coordination compounds (Chapter IR-9), and organometallic compounds (Chapter IR-10). Overall, the emphasis on additive nomenclature (generalized from the classical nomenclature of coordination compounds), which was already apparent in Red Book I, is reinforced here. Examples are even included of organic compounds, from the borderline between inorganic and organic chemistry, which may be conveniently named using additive nomenclature (although their PINs will be different).
One important addition in this book is Chapter IR-10 on Organometallic Compounds. The separation of this material from Coordination Compounds (Chapter IR-9) reflects the huge growth in importance of organometallic chemistry and the very different problems associated with the presence of p-bonded ligands. Chapter IR-9 is also considerably changed (cf. Red Book I, Chapter I-10). This revised chapter includes a clarification of the use of the Z and k conventions in coordination and organometallic compounds (Section IR-184.108.40.206); new rules for the ordering of central atoms in names of polynuclear compounds (Section IR-220.127.116.11); the bringing together of sections on configuration (Section IR-9.3) and their separation from those on constitution (Section IR-9.2); and the addition of polyhedral symbols for T-shaped (Section IR-18.104.22.168) and see-saw (Section IR-22.214.171.124) molecules, along with guidance on how to choose between these shapes and those of closely related structures (Section IR-126.96.36.199).
The reader facing the problem of how to name a given compound or species may find help in several ways. A flowchart is provided in Section IR-188.8.131.52, which will in most cases guide the user to a section or chapter where rules can be found for generating at least one possible name; a second flowchart is given in Section IR-9.2.1 to assist in the application of additive nomenclature, specifically to coordination and organometallic compounds. A more detailed subject index is also provided, as is an extended guide to possible alternative names of a wide range of simple inorganic compounds, ions and radicals.
* In IUPAC circles, this book (including former editions) is commonly referred to as the Red Book.
last modified 28 October 2005.
Copyright © 2003-2005 International Union of Pure and
Questions regarding the website, please contact [email protected]