Title: fundamental absorption
Long Title: IUPAC Gold Book - fundamental absorption
DOI: 10.1351/goldbook.14016
Status: current

Definition
Absorption of ultraviolet, visible, or infrared radiation in semiconductors and insulators inducing optical transitions of electrons originating exclusively from the valence band to the conduction band to yield free electron-hole pairs and/or exciton absorption bands.

Related Term
- extrinsic absorption: https://goldbook.iupac.org//terms/view/14010

Source
- PAC, 2011, 83, 931. 'Glossary of terms used in photocatalysis and radiation catalysis (IUPAC Recommendations 2011)' on page 954 (https://doi.org/10.1351/PAC-REC-09-09-36)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/14016/html
- json: https://goldbook.iupac.org/terms/view/14016/json
- xml: https://goldbook.iupac.org/terms/view/14016/xml

Citation: Citation: 'fundamental absorption' 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.14016
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Accessed: 2026-06-29T14:56:11+00:00