Geometry of (22)S/Cu(001) determined with use of angle-resolved-photoemission extended fine structure

Journal Article · Sun Mar 15 04:00:00 EST 1987 · Phys. Rev. B: Condens. Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.35.3773· OSTI ID:6986599

Bahr, C C; Barton, J J; Hussain, Z; Robey, S W; Tobin, J G; Shirley, D A

We have measured the adsorption geometry for the (2 x 2)S/Cu(001) surface, including the reconstruction and relaxation of the copper substrate. Multiple-scattering spherical-wave calculations were compared with angle-resolved-photoemission extended-fine-structure data and these results were then compared with a Fourier analysis of the data. The sulfur atoms are located in the fourfold hollow site, with a S--Cu bond distance of 2.26(1) A. With (1/4) monolayer ''p(2 x 2)'' sulfur coverage the symmetry of the copper substrate is necessarily lowered from (1 x 1) to (2 x 2). Accordingly, the sulfur adsorption induces reconstruction and relaxation of the two topmost Cu layers. All the movement occurs in Cu/sub 5/S moieties, as if the surface were forming Cu/sub 5/S clusters embedded in the bulk. The first-layer Cu atoms are shifted approx. =0.06 A towards the third Cu layer and 0.05(2) A laterally towards S. The second-layer Cu atoms under S atoms mimic the surface texture, in that they are 0.13 A farther from the third layer than the bulk spacing would predict. Second-layer Cu atoms under fourfold open sites are close to positions predicted by the bulk spacing. Details of the data analysis and extraction of surface-structural parameters are presented.

• Research Organization: Materials and Molecular Research Division, Lawrence Berkeley Laboratory, University of California, Berkeley, California 94720 and Department of Chemistry and Department of Physics, University of California, Berkeley, California 94720
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 6986599
• Journal Information: Phys. Rev. B: Condens. Matter; (United States), Journal Name: Phys. Rev. B: Condens. Matter; (United States) Vol. 35:8; ISSN PRBMD
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360102* -- Metals & Alloys-- Structure & Phase Studies
ADSORPTION
BOND LENGTHS
CONFIGURATION
COPPER
DIMENSIONS
ELECTRON SPECTROSCOPY
ELEMENTS
LENGTH
METALS
NONMETALS
PHOTOELECTRON SPECTROSCOPY
RELAXATION
RESOLUTION
SORPTION
SORPTIVE PROPERTIES
SPECTROSCOPY
SUBSTRATES
SULFUR
SURFACE PROPERTIES
TRANSITION ELEMENTS