Term: term
https://doi.org/10.1351/goldbook.T06273

Definition:
A set of levels which have the same electron configuration and the same value of the quantum numbers for total spin S and total orbital angular momentum L.

Related Terms:
1) angular momentum (http://doi.org/10.1351/goldbook.A00353).
2) electron configuration (http://doi.org/10.1351/goldbook.C01248).

Source: PAC, 1991, 63, 735. 'Nomenclature, symbols, units and their usage in spectrochemical analysis - VIII. Nomenclature system for X-ray spectroscopy (Recommendations 1991)' on page 737 (https://doi.org/10.1351/pac199163050735)

Citation: 'term' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.T06273

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.

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.