The (22 x √3) reconstruction of the Au(111) surface was modelled using a priori density-functional theory simulations involving use of Born-Oppenheimer molecular dynamics and simulated annealing procedures. The reconstruction was exothermic by 0.43eV per surface cell. Domains with surface atoms locating above fcc, hcp, and bridge sites of the second layer were produced, in quantitative agreement with experimental observations. While the reconstruction occurred to reduce the surface stresses created by cleavage of the bulk metal by minimizing the surface gold-gold interatomic separations, excess contraction appeared to be associated with the bridge domains, causing them to stand out and form ridges above the surface. However, the chemical activity of the surface was reduced as the local surface density increases, making the fcc domain the most active part while the hcp domain and bridge ridges were less active.

Simulation of the Au(111)-(22x√3) Surface Reconstruction. Y.Wang, N.S.Hush, J.R.Reimers: Physical Review B, 2007, 75[23], 233416 (4pp)