Anisotropy analysis of the surface stress in Ag stepped surfaces with the modified embedded atom method

Abstract

AbstractThe surface stresses in Ag stepped surfaces (910), (710), (510), (410), (310), (210), (320), (430) and (540) have been calculated by using the modified embedded atom method (MEAM). The surface stresses in the surface plane τxx (along the step edge) and τyy (normal to the step edge) have similar orders of magnitude as the surface energy. For surfaces having the (100) and (110) terraces, the change of τxx and τyy is very small and the variation of the surface energy is smooth. The stress τzz (normal to the surface plane) is always tensile in the unrelaxed state. The linear variation of the change in surface energy per unit change in elastic strain ${\partial \gamma\over \partial \varepsilon_{xx}}$, ${\partial \gamma\over \partial \varepsilon_{yy}}$ and ${\partial \gamma\over \partial \varepsilon_{zz}}$ (i.e. τxx − γ, τyy − γ and τzz) with the angle α between the (hk0) and (100) planes has a turning point corresponding to the (210) surface. The anisotropic ratio in the stepped surface having the (110) terrace is larger than that having the (100) terrace, and the wider the (110) terrace or the narrower the (100) terrace, the larger the ratio τyy/τxx. Copyright © 2006 John Wiley & Sons, Ltd.