Title: decadic absorbance
Long Title: IUPAC Gold Book - decadic absorbance
DOI: 10.1351/goldbook.D01536
Status: current
Index: quantity

Definition
The negative decadic logarithm of one minus absorptance as measured on a uniform sample: \[A=- \log _{10}(1- \alpha )\]

Related Term
- absorptance: https://dev.goldbook.iupac.org/terms/view/A00035

Source
- PAC, 1985, 57, 105. 'Names, symbols, definitions and units of quantities in optical spectroscopy (Recommendations 1984)' on page 116 (https://doi.org/10.1351/pac198557010105)

Other Outputs
- html: https://dev.goldbook.iupac.org/terms/view/D01536/html
- json: https://dev.goldbook.iupac.org/terms/view/D01536/json
- xml: https://dev.goldbook.iupac.org/terms/view/D01536/xml

Citation: Citation: 'decadic absorbance' 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.D01536
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Accessed: 2026-06-13T01:49:22+00:00