Using the crystal curvature technique, measurements were made of the change in surface stress on Cu(100) induced by oxygen adsorption to produce, at 300K, a c(2 x 2) overlayer phase, and at 500K, the (√2 x √2)R45° missing-row reconstructed phase. Density functional theory slab calculations were also performed for the absolute surface stress of the clean Cu(100) surface and these two chemisorbed oxygen phases. Both experiment and theory show that oxygen adsorption led to a compressive change in the surface stress that was larger for the c(2 x 2) overlayer (experiment: –1.0N/m; theory: –3.07N/m) than for the missing-row reconstruction (experiment: –0.6N/m; theory: –2.03N/m). Furthermore, the density functional theory calculations showed that the absolute compressive surface stress of the c(2 x 2) phase of –1.18N/m was lowered by the reconstruction to an average value of –0.14N/m. These results indicated that surface stress reduction played a role in causing the reconstruction.

Adsorbate-Induced Surface Reconstruction and Surface-Stress Changes in Cu(100)/O - Experiment and Theory. M.J.Harrison, D.P.Woodruff, J.Robinson, D.Sander, W.Pan, J.Kirschner: Physical Review B, 2006, 74[16], 165402 (7pp)