Please use this identifier to cite or link to this item: http://repositorio.unicamp.br/jspui/handle/REPOSIP/72941
Type: Artigo
Title: XPS and XAES study of Ag–Pd and Cu–Ni alloys: spectra, shifts and electronic structure information
Author: Barbieri, P. F.
Siervo, A. de
Carazzolle, M. F.
Landers, R.
Kleiman, G. G.
Abstract: The problem of determining the electronic structure of random metallic alloys is of fundamental importance. Although it represents one of the simplest situations beyond that of perfect crystals, it presents difficult challenges for electronic structure theory. We report a study of Ag-Pd and Cu-Ni alloys employing X-ray photoemission spectroscopy (XPS) and X-ray excited auger spectroscopy (XAES) utilizing conventional radiation sources We compare experimentally measured XPS shifts in Ag-Pd with recently reported calculations and show that, although the Pd shift appears to be consistent with a complete screening picture, it is not possible to reach such an unambiguous conclusion for the Ag shift on the basis of such a comparison. By applying a previously derived technique to the XPS and XAES energy shifts, we demonstrate that charge transfer is essentially absent in these systems and we derive the changes in d and sp electronic occupations of the alloy components, in agreement with experimental Auger parameter shifts. We note that the Ag d-band loses electrons in dilute Ag alloys and gains electrons otherwise, in contrast with any other alloy system studied to date.
The problem of determining the electronic structure of random metallic alloys is of fundamental importance. Although it represents one of the simplest situations beyond that of perfect crystals, it presents difficult challenges for electronic structure theory. We report a study of Ag–Pd and Cu–Ni alloys employing X-ray photoemission spectroscopy (XPS) and X-ray excited auger spectroscopy (XAES) utilizing conventional radiation sources We compare experimentally measured XPS shifts in Ag–Pd with recently reported calculations and show that, although the Pd shift appears to be consistent with a complete screening picture, it is not possible to reach such an unambiguous conclusion for the Ag shift on the basis of such a comparison. By applying a previously derived technique to the XPS and XAES energy shifts, we demonstrate that charge transfer is essentially absent in these systems and we derive the changes in d and sp electronic occupations of the alloy components, in agreement with experimental Auger parameter shifts. We note that the Ag d-band loses electrons in dilute Ag alloys and gains electrons otherwise, in contrast with any other alloy system studied to date.
Subject: Espectros Auger
Espectroscopia fotoeletrônica de raio X
Estrutura eletrônica
Country: Holanda
Editor: Elsevier
Citation: Journal Of Electron Spectroscopy And Related Phenomena. Elsevier Science Bv, v. 135, n. 41700, n. 113, n. 118, 2004.
Rights: fechado
Identifier DOI: 10.1016/j.elspec.2004.02.121
Address: https://www.sciencedirect.com/science/article/pii/S0368204804001458
Date Issue: 2004
Appears in Collections:IFGW - Artigos e Outros Documentos

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