Title: optical rotatory power
Long Title: IUPAC Gold Book - optical rotatory power
DOI: 10.1351/goldbook.O04313
Status: current

Definition
Angle of optical rotation divided by the optical path length through the medium and by either the mass concentration of the substance giving the specific optical rotatory power \(\left[\alpha \right]_{\lambda }^{\theta }\) or by amount concentration, giving the molar optical rotatory power, \(\alpha _{\rm{m}}\).

Related Terms
- Angle of optical rotation: https://goldbook.iupac.org//terms/view/A00348
- amount concentration: https://goldbook.iupac.org//terms/view/A00295
- rotatory power: https://goldbook.iupac.org//terms/view/R05415

Source
- Green Book, 2nd ed., p. 33 (https://goldbook.iupac.org/files/pdf/green_book_2ed.pdf)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/O04313/html
- json: https://goldbook.iupac.org/terms/view/O04313/json
- xml: https://goldbook.iupac.org/terms/view/O04313/xml

Citation: Citation: 'optical rotatory power' 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.O04313
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Accessed: 2026-06-20T02:46:08+00:00