05412 IUPAC Gold Book - rotational frequency 10.1351/goldbook.R05412 R05412 current quantity 1 The number of rotations divided by time: \[f_{\rm{rot}}=\frac{\rm{d}N}{\rm{d}t}\] The synonyms rate of rotation, rate of revolution, centrifugal speed, centrifugation speed, and the traditional units of rotational frequency such as revolutions per minute, r.p.m., ppm, \(\rm{rev min}^{-1}\), \(\rm{r min}^{-1}\), are not recommended. PAC, 1994, 66, 897. 'Quantities and units for centrifugation in the clinical laboratory (IUPAC Recommendations 1994)' on page 904 (https://doi.org/10.1351/pac199466040897) PAC, 1996, 68, 957. 'Glossary of terms in quantities and units in Clinical Chemistry (IUPAC-IFCC Recommendations 1996)' on page 991 (https://doi.org/10.1351/pac199668040957) https://goldbook.iupac.org/terms/view/R05412/html https://goldbook.iupac.org/terms/view/R05412/json https://goldbook.iupac.org/terms/view/R05412/plain Citation: 'rotational frequency' 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.R05412 The IUPAC Gold Book is licensed under Creative Commons Attribution-ShareAlike CC BY-SA 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/) for individual terms. If you are interested in licensing the Gold Book for commercial use, please contact the IUPAC Executive Director at executivedirector@iupac.org . The International Union of Pure and Applied Chemistry (IUPAC) is continuously reviewing and, where needed, updating terms in the Compendium of Chemical Terminology (the IUPAC Gold Book). Users of these terms are encouraged to include the version of a term with its use and to check regularly for updates to term definitions that you are using. 2026-05-12T02:09:22+00:00