Refinement of the Pd(111)+(r3xr3)R30degrees-CO structure usingautomated tensor LEED

Journal Article · Mon Nov 01 04:00:00 EST 1999 · Surface Science

OSTI ID:894398

Zasada, I; Van Hove, M A

The structure of Pd(111)+(root3xroot3)R30degrees-CO has beenrefined using automated tensor LEED, especially to optimizeadsorbate-induced relaxations in the substrate. The reanalysisconsiderably improves the best fit to experiment, while retaining most ofthe detailed features, compared to the last structural analysis performedon this system by "conventional" quantitative low-energy electrondiffraction (LEED). In particular, this study confirms that CO occupiesfcc-hollow sites. It finds an expansion of the top Pd-Pd interlayerspacing by 0.10(plus/minus)0.04 Angstrom, a contraction of the secondPd-Pd interlayer spacing by 0.02(plus/minus)0.04 Angstrom, and a possiblelateral enlargement by 0.1(plus/minus)0.1 Angstrom of the triangle of Pdatoms around the adsorption site. A somewhat small C-O interlayer spacingof 1.11(plus/minus)0.04 Angstrom is observed, but no clear CO tilt fromthe surface normal is detected (6(plus/minus)10 degrees).

• Research Organization: Ernest Orlando Lawrence Berkeley NationalLaboratory, Berkeley, CA (US)
• Sponsoring Organization: USDOE Director, Office of Science. Office of Basic EnergySciences. Division of Materials Sciences
• DOE Contract Number: AC02-05CH11231
• OSTI ID: 894398
• Report Number(s): LBNL--44370
• Journal Information: Surface Science, Journal Name: Surface Science Journal Issue: 3 Vol. 457
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
low-energy electron difffraction catalysis chemisorptionsurface relaxation palladium carbon monoxide single crystalsurface