{"term":{"id":"09358","title":"surface core-level shift","longtitle":"IUPAC Gold Book - surface core-level shift","doi":"10.1351\/goldbook.09358","code":"09358","status":"current","definitions":[{"id":1,"text":"Energy shift observed in core-level photoelectron spectroscopy arising from the reduced coordination of the surface or near-surface atoms compared to bulk atoms.","notes":{"1":"Surface core level shifts are often observed for single crystals and nanoparticles and depend on the crystal surface exposed. Shifts can be to lower or higher binding energy, depending on the band structure of the bulk solid. For the outermost atom layer, the shift can be as high as \\(\\pu{0.4 eV}\\). In X-ray photoelectron emission, the sampling depth is generally many atom layers when photoelectrons are detected with emission angles at, or close to, the surface normal. The shift for the outermost atom layer is thus seen most clearly at near-grazing emission angles. Separate energy shifts can be detected for the second and third atom layers from the surface."},"links":[{"term":"X-ray photoelectron emission","url":"https:\/\/goldbook.iupac.org\/\/terms\/view\/09348"}],"sources":["PAC, 2020, 92, 1781. 'Glossary of methods and terms used in surface chemical analysis (IUPAC Recommendations 2020)' on page 1831 (https:\/\/doi.org\/10.1515\/pac-2019-0404)"]}],"altoutputs":{"html":"https:\/\/goldbook.iupac.org\/terms\/view\/09358\/html","xml":"https:\/\/goldbook.iupac.org\/terms\/view\/09358\/xml","plain":"https:\/\/goldbook.iupac.org\/terms\/view\/09358\/plain"},"citation":"Citation: 'surface core-level shift' 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.09358","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":"2026-04-27T16:15:21+00:00"}}