Strain relaxation in small adsorbate islands: O on W(110)

Abstract

The stress-induced lattice changes in a p(1x2) ordered oxygen layer on W(110) are measured by low-energy electron diffraction. We have observed that small oxygen islands show a mismatch with the underlying lattice. Our results indicate that along [1-10] the average mismatch scales inversely with the island size as 1/L for all oxygen coverages up to 0.5 ML, while along [001] it is significant only for the smallest oxygen islands and scales as a higher power of the inverse island size. The behaviour along [1-10] is described by a one-dimensional finite-size Frenkel-Kontorova model. Using this model, together with calculated force constants, we make a quantitative estimate for the change of surface-stress upon oxygen adsorption. The result is consistent with our ab-initio calculations, which give a relative compressive stress of -4.72 N/m along [1-10] and a minute relative tensile stress of 0.15 N/m along [001]. The scaling along [001] is qualitatively explained as an effect induced by the lattice relaxation in the [1-10] direction.

22 pages, 5 figures

References in corpus (3)

• First principles calculation of structural and magnetic properties for Fe monolayers and bilayers on W(110)
• Ab initio calculations of adsorbate-induced stress on Ni(100)
• Surface magnetism of Rh(001) from LDA+U calculations

Cited by in corpus (7)

• Angle-resolved X-ray photoemission electron microscopy
• Stress induced stripe formation in Pd/W(110)
• Surface stress of Ni adlayers on W(110): the critical role of the surface atomic structure
• Temperature dependence of surface stress across an order-disorder transition: p(1x2)O/W(110)
• High-temperature oxygen monolayer structures on W(110) revisited
• Self-organization in Pd/W(110): interplay between surface structure and stress
• Stress engineering at the nanometer scale: Two-component adlayer stripes