14063 IUPAC Gold Book - physical pathway 10.1351/goldbook.14063 14063 current 1 Set of physical processes leading to the relaxation of the electronically excited system without chemical transformations. Examples are radiative and nonradiative relaxations in molecules and surface complexes from the excited state to the ground state, recombination and trapping of free charge carriers and recombination decay of trapped carriers (particularly, recombination decay of carriers trapped by surface-active centres). Radiative and nonradiative relaxations in molecules and surface complexes from the excited state to the ground state, recombination and trapping of free charge carriers and recombination decay of trapped carriers (particularly, recombination decay of carriers trapped by surface-active centres). PAC, 2011, 83, 931. 'Glossary of terms used in photocatalysis and radiation catalysis (IUPAC Recommendations 2011)' on page 976 (https://doi.org/10.1351/PAC-REC-09-09-36) https://goldbook.iupac.org/terms/view/14063/html https://goldbook.iupac.org/terms/view/14063/json https://goldbook.iupac.org/terms/view/14063/plain Citation: 'physical pathway' 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.14063 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. 2026-05-07T00:07:22+00:00