Title: physical pathway
Long Title: IUPAC Gold Book - physical pathway
DOI: 10.1351/goldbook.14063
Status: current

Definition
Set of physical processes leading to the relaxation of the electronically excited system without chemical transformations.

Note
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).

Example
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).

Source
- 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)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/14063/html
- json: https://goldbook.iupac.org/terms/view/14063/json
- xml: https://goldbook.iupac.org/terms/view/14063/xml

Citation: 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
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Accessed: 2026-05-31T05:22:45+00:00