Suppression of disorder broadening of core-level photoelectron lines in CuAu alloys by inhomogeneous lattice distortion
2009 (English)In: Physical Review B. Condensed Matter and Materials Physics, ISSN 1098-0121, E-ISSN 1550-235X, Vol. 79, no 1, 012201- p.Article in journal (Refereed) Published
Disorder broadening of core-level binding energies is a general effect observed in random alloys, and identifies an opportunity for studying specific local environments experimentally. Here we study it in an archetypical system: face-centered-cubic Cu50Au50. While the disorder broadening is clearly detectable at Au, at Cu it is below the detection limit. We supplement experiments by a theoretical study where we model the alloy by a large supercell constructed as a special quasirandom structure and calculate binding-energy shifts at all sites in the supercell. Theory shows that the suppression of the disorder broadening at Cu results from a delicate balance between the influence of local chemical environment and inhomogeneous lattice distortions on the site-resolved core-level shifts. Surprisingly, even larger relaxation-induced shifts are observed at Au sites.
Place, publisher, year, edition, pages
2009. Vol. 79, no 1, 012201- p.
copper alloys, core levels, electronic structure, gold alloys, photoelectron spectra
IdentifiersURN: urn:nbn:se:liu:diva-16832DOI: 10.1103/PhysRevB.79.012201OAI: oai:DiVA.org:liu-16832DiVA: diva2:174374