Phase behavior of Au and Pt surfaces

Conference · Sun Nov 01 04:00:00 EST 1992

OSTI ID:10180079

Gruebel, G ^[1]; Gibbs, D ^[2]; Zehner, D M ^[3]; Abernathy, D L; Mochrie, S G.J. ^[4]; Sandy, A R ^[5]

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1. European Synchrotron Radiation Facility, 38 - Grenoble (France). Experiments Div.
2. Brookhaven National Lab., Upton, NY (United States)
3. Oak Ridge National Lab., TN (United States)
4. Massachusetts Inst. of Tech., Cambridge, MA (United States). Dept. of Physics
5. Risoe National Lab., Roskilde (Denmark). Physics Dept.

We summarize the results of x-ray scattering studies of the Au(001) and Pt(001) surfaces between 300 K and their respective bulk melting temperatures (T{sub m}). Both surfaces exhibit three distinct structural phases. At high temperatures (0--88 T{sub m} < T < T{sub m} ) both surfaces are disordered. At a temperature of T/T{sub m} {minus} 0.88 there are reversible phase transformations to incommensurate, corrugated-hexagonal phases. Below T/T{sub m} {minus} 0.8 hexagonal domains rotate with respect to the substrate orientation. In Pt, the rotational transformation is continuous and shows mean-field behavior. In Au, the rotational transformation is mainly discontinuous.

• Research Organization: Oak Ridge National Lab., TN (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States); National Science Foundation, Washington, DC (United States)
• DOE Contract Number: AC05-84OR21400; AC02-76CH00016
• OSTI ID: 10180079
• Report Number(s): CONF-9210161--2; CONF-9210162--2; ON: DE92041021; CNN: Grant DMR-9119675
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360102
GOLD
PHASE STUDIES
PHASE TRANSFORMATIONS
PLATINUM
STRUCTURE AND PHASE STUDIES
SURFACE PROPERTIES
SURFACES
TEMPERATURE RANGE 0400-1000 K
TEMPERATURE RANGE 1000-4000 K
X-RAY DIFFRACTION