Peak in the electron spectrum, produced by quasi-elastically scattered electrons detected by an
electron spectrometer.
Notes: - All electrons that are scattered by atoms can be elastically scattered in the centre-of-mass frame, but energy losses that are typically less than \(\pu{1 eV}\) might be observed in the laboratory frame. These losses are generally significantly less than the measured energy width of the electrons in a primary-electron beam. Historically, and more generally, the scattering has been called “elastic”; however, the term quasi-elastic is now often used if the small change in energy that occurs on scattering is important.
- The energy and the energy broadening of the quasi-elastic peak are influenced by the recoil of the scatterer atoms, the energy distribution of the primary (incident) electrons, the scattering geometry, the acceptance geometry, and the response function of the electron spectrometer. The intensity of the elastic peak depends on the electron differential elastic scattering cross section and on the cross section for inelastic electron scattering at the particular beam energy of the primary-electrons and in the given scattering geometry, including the probability of surface excitations.
See also: Elastic peak electron spectroscopy
Source:
PAC, 2020, 92, 1781. 'Glossary of methods and terms used in surface chemical analysis (IUPAC Recommendations 2020)' on page 1824 (https://doi.org/10.1515/pac-2019-0404)