Oxygen-induced restructuring with release of gold atoms from Au(111)

Abstract

Adsorption of oxygen atoms, achieved via electron-induced dissociation of nitrogen dioxide, induces restructuring of the ``herringbone'' to a striped, soliton-wall structure accompanied by release of gold from the ``elbows'' in the herringbone structure. The number density of ``elbows'' (dislocations corresponding to a change in direction of the reconstruction) decreases as a function of increasing atomic oxygen coverage while the long range order observed in low energy electron diffraction (LEED) changes from $(\sqrt{3}\ifmmode\times\else\texttimes\fi{}22)$--rec. to $(1\ifmmode\times\else\texttimes\fi{}22)$ in the limit of saturation coverage. Small islands and serrated step edges were formed due to the release of gold atoms from elbow sites of Au(111). The overall structural change of the Au(111) surface may result from the reduction of anisotropy related to the tensile stress relief of the Au(111) surface by oxygen atoms.