Term: principal moments of inertia https://doi.org/10.1351/goldbook.P04848 Definition: Moments of inertia about the principal axes of the molecule chosen so as to make all the products of inertia equal to zero, IA ≤ IB ≤ IC. Source: Green Book, 2nd ed., p. 23 (https://goldbook.iupac.org/files/pdf/green_book_2ed.pdf) Citation: 'principal moments of inertia' 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.P04848 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.