Phase behavior of Au and Pt surfaces

Conference · Wed Jan 01 04:00:00 EST 1992

OSTI ID:7253691

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 De

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: DOE; NSF; USDOE, Washington, DC (United States); National Science Foundation, Washington, DC (United States)
• DOE Contract Number: AC05-84OR21400; AC02-76CH00016
• OSTI ID: 7253691
• Report Number(s): CONF-9210161-2; CONF-9210162--2; ON: DE92041021; CNN: DMR-9119675
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360102* -- Metals &amp; Alloys-- Structure &amp; Phase Studies
COHERENT SCATTERING
DIFFRACTION
ELEMENTS
GOLD
METALS
PHASE STUDIES
PHASE TRANSFORMATIONS
PLATINUM
PLATINUM METALS
SCATTERING
SURFACE PROPERTIES
SURFACES
TEMPERATURE RANGE
TEMPERATURE RANGE 0400-1000 K
TEMPERATURE RANGE 1000-4000 K
TRANSITION ELEMENTS
X-RAY DIFFRACTION