Isotopically Modified Compounds

R-8.1.2 Atomic symbols

The atomic symbols used in the nuclide symbols are those given in IUPAC Nomenclature of Inorganic Chemistry. In the nuclide symbol, the atomic symbol is printed in roman type, italicized atomic symbols being reserved for letter locants, as is customary in organic chemical nomenclature.

Note: For the hydrogen isotopes protium, deuterium, and tritium, the nuclide symbols , , and , respectively, are used. The symbols D and T for and , respectively, may be used, but not when other modifying nuclides are also present, because this may cause difficulties in alphabetic ordering of the nuclide symbols in the isotopic descriptor. Although the symbols d and t have been and are still used in place of and in names formed according to the Boughton system (see R-8.0), in no other cases are lower-case letters used as atomic symbols. Therefore, the use of d and t in chemical nomenclature outside if the Boughton system is not recommended.

R-8.1.3 Isotopically unmodified copounds
R-8.1.4 Isotopically modified compounds

This HTML reproduction is as close as possible to the published version [see IUPAC, Commission on Nomenclature of Organic Chemistry. A Guide to IUPAC Nomenclature of Organic Compounds (Recommendations 1993), 1993, Blackwell Scientific publications, Copyright 1993 IUPAC]. If you need to cite these rules please quote this reference as their source.

Published with permission of the IUPAC by Advanced Chemistry Development, Inc.,, +1(416)368-3435 tel, +1(416)368-5596 fax. For comments or suggestions please contact