Title: term symbols
Long Title: IUPAC Gold Book - term symbols
DOI: 10.1351/goldbook.T06277
Status: current

Definition
Symbols characterizing the states of atoms and molecules in terms of multiplicity, symmetry of the total electronic wavefunction, and sometimes total (orbital + spin) angular momentum. Examples: \(^{2}\rm{P}_{1/2}\) denotes an atomic state of multiplicity 2 (doublet), electron orbital angular momentum quantum number \(L=1\), and orbital plus spin angular momentum quantum number \(J=\frac{1}{2}\).

Related Term
- angular momentum: https://goldbook.iupac.org//terms/view/A00353

Source
- Green Book, 2nd ed., p. 28 (https://goldbook.iupac.org/files/pdf/green_book_2ed.pdf)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/T06277/html
- json: https://goldbook.iupac.org/terms/view/T06277/json
- xml: https://goldbook.iupac.org/terms/view/T06277/xml

Citation: Citation: 'term symbols' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351/goldbook.T06277
License: The IUPAC Gold Book is licensed under Creative Commons Attribution-ShareAlike CC BY-SA 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/) for individual terms.
Collection: If you are interested in licensing the Gold Book for commercial use, please contact the IUPAC Executive Director at executivedirector@iupac.org .
Disclaimer: The International Union of Pure and Applied Chemistry (IUPAC) is continuously reviewing and, where needed, updating terms in the Compendium of Chemical Terminology (the IUPAC Gold Book). Users of these terms are encouraged to include the version of a term with its use and to check regularly for updates to term definitions that you are using.
Accessed: 2026-06-20T02:46:08+00:00