Title: molar Napierian absorption coefficient
Long Title: IUPAC Gold Book - molar Napierian absorption coefficient
DOI: 10.1351/goldbook.08270
Status: current

Definition
Napierian absorbance (\(A_{\rm{e}}\)) divided by path-length (\(l\)) and amount concentration (\(c\)). \(\kappa = A_{\rm{e}}/(cl)\).


Related Terms
- Napierian absorbance: https://goldbook.iupac.org//terms/view/08272
- linear Napierian absorption coefficient: https://goldbook.iupac.org//terms/view/08265
- molar decadic absorption coefficient: https://goldbook.iupac.org//terms/view/08269

Source
- PAC, 2021, 93, 647. 'Glossary of methods and terms used in analytical spectroscopy (IUPAC Recommendations 2019)' on page 667 (https://doi.org/10.1515/pac-2019-0203)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/08270/html
- json: https://goldbook.iupac.org/terms/view/08270/json
- xml: https://goldbook.iupac.org/terms/view/08270/xml

Citation: Citation: 'molar Napierian absorption coefficient' 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.08270
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Accessed: 2026-05-30T13:17:16+00:00