THE SURFACE-COMPOSITION, STRUCTURE AND OXYGEN-INDUCED (2X1) RECONSTRUCTION OF CU3PT(110)

Citation
Yg. Shen et al., THE SURFACE-COMPOSITION, STRUCTURE AND OXYGEN-INDUCED (2X1) RECONSTRUCTION OF CU3PT(110), Surface science, 410(1), 1998, pp. 1-14
Citations number
44
Categorie Soggetti
Chemistry Physical
Journal title
ISSN journal
00396028
Volume
410
Issue
1
Year of publication
1998
Pages
1 - 14
Database
ISI
SICI code
0039-6028(1998)410:1<1:TSSAO(>2.0.ZU;2-S
Abstract
The surface composition, structure, and oxygen-induced reconstruction of Cu3Pt(110) have been investigated by low-energy ion scattering, rec oiling spectrometry, and low-energy electron diffraction. The surface composition of the top two layers was determined from Li+ single-scatt ering intensities using selective scattering geometries with calibrati on measurements on reference standards. Under thermal equilibrium cond itions, the measurements consistently showed a surface composition of 82% Cu-18% Pt in the first layer, while the second layer was composed almost entirely of Cu. From computer simulations and analysis of the s hadowing critical edges, the first interlayer spacing was found to be contracted by about 6+/-2%. whereas the surface Pt atoms were buckled outward by 0.1+/-0.06 Angstrom. Adsorption of oxygen on the clean Cu3P t(110) surface at room temperature followed by subsequent annealing le ads to a (2 x 1) reconstruction. By Li+ ion scattering and negative O- recoil measurements the oxygen-induced structure was determined to be a missing-row type reconstruction which involves loss of Pt from the first layer in a thermally activated place exchange with Cu atoms. The first interlayer spacing was expanded by 23+/-10% relative to the ide al spacing, while the O atoms were located 0.1+/-0.1 Angstrom below th e first Cu layer. The structural features found are discussed and comp ared with previous results on the Cu(110)-(2 x 1)-O and Cu3Au(110)-(2 x 1)-O surfaces. (C) 1998 Elsevier Science B.V. All rights reserved.