Pokrovsky-Talapov commensurate-incommensurate transition in the CO/Pd(100) system

Journal Article · Sun Dec 01 04:00:00 EST 1996 · Physical Review, B: Condensed Matter

DOI:https://doi.org/10.1103/PhysRevB.54.17097· OSTI ID:404804

Schuster, R ^[1]; Robinson, I K ^[2]; Kuhnke, K ^[3]; Ferrer, S; Alvarez, J ^[4]; Kern, K ^[3]

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1. Fritz-Haber-Institut der Max-Planck-Gesellschaft, D-14195 Berlin (Germany)
2. Physics Department, University of Illinois, Urbana, Illinois 61801 (United States)
3. Institute de Physique Experimentale, Ecole Polytechnique Federale de Lausanne, CH-1015 Lausanne (Switzerland)
4. European Synchrotron Radiation Facility, F-38043 Grenoble (France)

X-ray-diffraction measurements have been carried out for a monolayer of CO on the Pd(100) surface. Because of equilibrium with the gas phase, at constant pressure a series of structures is formed with varying temperature (varying coverage). One structure at 350 K selected for crystallographic analysis, is found to be a commensurate lattice with {ital p}2{ital gg} symmetry of CO molecules bound in substrate-bridge sites. The vibration amplitudes of the molecules are substantially larger in-plane than out-of-plane. Upon cooling, a phase transition is crossed beyond which the structure becomes incommensurate. Symmetry considerations and the measured exponent of 0.5{plus_minus}0.05 establish this transition to be in the Pokrovsky-Talapov universality class. {copyright} {ital 1996 The American Physical Society.}

• OSTI ID: 404804
• Journal Information: Physical Review, B: Condensed Matter, Journal Name: Physical Review, B: Condensed Matter Journal Issue: 23 Vol. 54; ISSN PRBMDO; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
ADSORBATES
CARBON MONOXIDE
CHEMISORPTION
CRITICAL EXPONENTS
DOMAIN WALLS
PALLADIUM
PHASE TRANSFORMATIONS
SORPTIVE PROPERTIES
TEMPERATURE RANGE 273-400 K
THIN FILMS
X-RAY DIFFRACTION