{"term":{"id":"02723","title":"half-width","longtitle":"IUPAC Gold Book - half-width","doi":"10.1351\/goldbook.H02723","code":"H02723","status":"current","initialism":"<em>initialism<\/em>: FWHM","synonym":"<em>synonym<\/em>: full width at half maximum","definitions":[{"id":1,"text":"The full width of a spectral band at a height equal to half of the height at the band maximum. Also known as full width at half maximum (FWHM). The dimension of band width should be either inverse length (wavenumbers) or inverse time (frequencies) so that the values give an indication of the energies. Note the hyphen in half-width. Half bandwidth has the meaning of half-width at half maximum.","contexts":[],"sources":["PAC, 1996, 68, 2223. 'Glossary of terms used in photochemistry (IUPAC Recommendations 1996)' on page 2245 (https:\/\/doi.org\/10.1351\/pac199668122223)"],"seealso":["Orange Book, 2nd ed., p. 226 (https:\/\/media.iupac.org\/publications\/analytical_compendium\/)"]}],"altoutputs":{"html":"https:\/\/goldbook.iupac.org\/terms\/view\/H02723\/html","xml":"https:\/\/goldbook.iupac.org\/terms\/view\/H02723\/xml","plain":"https:\/\/goldbook.iupac.org\/terms\/view\/H02723\/plain"},"citation":"Citation: 'half-width' 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.H02723","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":"2026-05-18T10:44:37+00:00"}}