{"term":{"id":"08735","title":"monoisotopic element","longtitle":"IUPAC Gold Book - monoisotopic element","doi":"10.1351\/goldbook.08735","code":"08735","status":"current","definitions":[{"id":1,"text":"Chemical element having only one stable nuclide.","notes":{"1":"There are 26 elements that follow the definition: \\(\\ce{^{9}Be}\\), \\(\\ce{^{19}F}\\), \\(\\ce{^{23}Na}\\), \\(\\ce{^{27}Al}\\), \\(\\ce{^{31}P}\\), \\(\\ce{^{45}Sc}\\), \\(\\ce{^{51}V}\\), \\(\\ce{^{55}Mn}\\), \\(\\ce{^{59}Co}\\), \\(\\ce{^{75}As}\\), \\(\\ce{^{85}Rb}\\), \\(\\ce{^{89}Y}\\), \\(\\ce{^{93}Nb}\\), \\(\\ce{^{103}Rh}\\), \\(\\ce{^{113}In}\\), \\(\\ce{^{127}I}\\), \\(\\ce{^{133}Cs}\\), \\(\\ce{^{139}La}\\), \\(\\ce{^{141}Pr}\\), \\(\\ce{^{153}Eu}\\), \\(\\ce{^{159}Tb}\\), \\(\\ce{^{165}Ho}\\), \\(\\ce{^{169}Tm}\\), \\(\\ce{^{175}Lu}\\), \\(\\ce{^{185}Re}\\), \\(\\ce{^{197}Au}\\).","2":"General usage of the term 'monoisotopic' refers to the 21 elements with one isotope determining their relative atomic masses, i.e. \\(\\ce{^{9}Be}\\), \\(\\ce{^{19}F}\\), \\(\\ce{^{23}Na}\\), \\(\\ce{^{27}Al}\\), \\(\\ce{^{31}P}\\), \\(\\ce{^{45}Sc}\\), \\(\\ce{^{55}Mn}\\), \\(\\ce{^{59}Co}\\), \\(\\ce{^{75}As}\\), \\(\\ce{^{89}Y}\\), \\(\\ce{^{93}Nb}\\), \\(\\ce{^{103}Rh}\\), \\(\\ce{^{127}I}\\), \\(\\ce{^{133}Cs}\\), \\(\\ce{^{141}Pr}\\), \\(\\ce{^{159}Tb}\\), \\(\\ce{^{165}Ho}\\), \\(\\ce{^{169}Tm}\\), \\(\\ce{^{197}Au}\\), \\(\\ce{^{209}Bi}\\), \\(\\ce{^{231}Pa}\\)."},"sources":["PAC, 2021, 93, 69. 'Vocabulary of radioanalytical methods (IUPAC Recommendations 2020)' on page 87 (https:\/\/doi.org\/10.1515\/pac-2019-0302)"]}],"altoutputs":{"html":"https:\/\/goldbook.iupac.org\/terms\/view\/08735\/html","xml":"https:\/\/goldbook.iupac.org\/terms\/view\/08735\/xml","plain":"https:\/\/goldbook.iupac.org\/terms\/view\/08735\/plain"},"citation":"Citation: 'monoisotopic element' 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.08735","license":"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.","collection":"If you are interested in licensing the Gold Book for commercial use, please contact the IUPAC Executive Director at executivedirector@iupac.org .","disclaimer":"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.","accessed":"2026-05-18T03:45:48+00:00"}}