The deconstruction of the $\mathrm{Au}\{110\}-(1\mathrm{}\times 2)$ missing-row (MR) surface has been studied by variable temperature scattering and recoiling imaging spectrometry (SARIS). SARIS images were acquired over the range of 298–720 K and for an amorphousized surface produced by high-dose ${\mathrm{Ar}}^{+}$ sputtering. The sharp, anisotropic features observed in the images from the ordered $(1\mathrm{}\times 2)$ surface at 298 K change monotonically with increasing temperature into broadened, more featureless images in which the first-layer blocking arcs shift to very low exit angle values. The basic features of the $(1\mathrm{}\times 2)$ MR structure are still observed even near 700 K where three-dimensional roughening begins. These $(1\mathrm{}\times 2)$ features are completely obliterated on the sputtered amorphousized surface, depicting a surface that is dominated by three-dimensional roughening. Classical ion trajectory simulations using the scattering and recoiling imaging code are used to probe the effects of vibrational amplitude and conversion to a $(1\mathrm{}\times 1)$ structure. The results accentuate the remarkable stability of the $(1\mathrm{}\times 2)$ MR structure up to the roughening temperature and exclude early proposals of an order-disorder transition via lattice gas formation. The findings are in agreement with more recent models in which roughening induces a simultaneous deconstruction transition.

• Received 2 March 1998

DOI:https://doi.org/10.1103/PhysRevB.58.9990