Accession Number : ADA191263

Title :   In-Plane Structure of Underpotentially Deposited Copper on Gold (111) Determined by Surface EXAFS (Extended X-Ray Absorption Fine Structure).

Descriptive Note : Interim technical rept.,

Corporate Author : PUERTO RICO UNIV RIO PIEDRAS DEPT OF PHYSICS

Personal Author(s) : Melroy, O R ; Samant, M G ; Borges, G L ; Gordon, J G , II ; Blum, Lesser

PDF Url : ADA191263

Report Date : 28 Jan 1988

Pagination or Media Count : 23

Abstract : The Surface Extended X Ray Absorption Fine Structure (SEFAFS) spectrum of an electrochemically deposited ad-layer of copper on a gold (111) electrode immersed in solution and under potential control was obtained by employing fluorescence detection and grazing incidence geometry. The x-rays were polarized parallel to the plane of the gold surface. Two peaks were observed in the radial distribution function, indicating two different near neighbors for copper. The near neighbors were determined to be gold at 2.58 plus or minus 0.03 angstrom and copper at 2.92 plus or minus 0.03 angstroms. The copper-copper distance is identical to the gold-gold lattice spacing showing that at full coverage, the copper ad-layer forms at 1 x 1 commensurate layer on the gold (111) substrate. The intensity of the gold-copper scattering relative to the copper-copper suggests the copper atoms sit in 3 fold hollows sites.

Descriptors :   *COPPER, *DEPOSITION, *GOLD, ATOMS, CONTROL, DETECTION, DISTRIBUTION FUNCTIONS, FLUORESCENCE, GEOMETRY, GRAZING, LAYERS, RADIUS(MEASURE), SPATIAL DISTRIBUTION, SUBSTRATES, SURFACES

Subject Categories : Inorganic Chemistry
      Physical Chemistry

Distribution Statement : APPROVED FOR PUBLIC RELEASE