  We have calculated the surface stress induced on adsorption of c(2x2)
overlayers of O and C, using first principles electronic structure calculations
based on density functional theory within the local density approximation(LDA)
and non-local pseudopotentials. Most remarkable result is found in the case of
the C overlayer which introduces a large compressive stress, while that on
clean Ni(100) and that in the presence of the O overlayer are found to be
tensile and smaller in comparison. We find a correlation between the height of
the C overlayer and the resulting clock reconstruction of Ni(100) but no
specific relationship between surface stress and surface reconstruction. We
discuss our results in the context of experimental data, and insights from
electronic structure calculations.

Materials Science