05353 IUPAC Gold Book - retardation factor 10.1351/goldbook.R05353 R05353 current synonym: RF value quantity 1 Ratio of the distance travelled by the centre of the spot to the distance simultaneously travelled by the mobile phase: \[R_{\rm{F}}=\frac{b}{a}\] By definition the \(R_{\rm{F}}\) values are always less than unity. They are usually given to two decimal places. In order to simplify this presentation the \(hR_{\rm{F}}\) values may be used: they correspond to the \(R_{\rm{F}}\) values multiplied by 100. Ideally, \(R_{\rm{F}}\) values are identical to the \(R\) values used in column chromatography. column chromatography https://goldbook.iupac.org//terms/view/C01182 PAC, 1993, 65, 819. 'Nomenclature for chromatography (IUPAC Recommendations 1993)' on page 845 (https://doi.org/10.1351/pac199365040819) https://goldbook.iupac.org/terms/view/R05353/html https://goldbook.iupac.org/terms/view/R05353/json https://goldbook.iupac.org/terms/view/R05353/plain Citation: 'retardation factor' 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.R05353 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. 2026-07-13T14:01:42+00:00