15431 IUPAC Gold Book - path length 10.1351/goldbook.15431 15431 current 1 Number of polymer main-chain (backbone) atoms between two subunits. Where a ring or ring system constitutes all or part of a path between two subunits, the shortest continuous chain of atoms in the ring or ring system is selected. PAC, 2008, 80, 201. 'Structure-based nomenclature for cyclic organic macromolecules (IUPAC Recommendations 2008)' on page 205 (https://doi.org/10.1351/pac200880020201) https://goldbook.iupac.org/terms/view/15431/html https://goldbook.iupac.org/terms/view/15431/json https://goldbook.iupac.org/terms/view/15431/plain Citation: 'path length' 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.15431 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. If you are interested in licensing the Gold Book for commercial use, please contact the IUPAC Executive Director at executivedirector@iupac.org . 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. 2026-06-28T18:56:20+00:00