Elastic stress domains and the herringbone reconstruction on Au(111)

We suggest that the herringbone reconstruction of the Au(111) surface results from the spontaneous formation of ``stress domains.'' The surface is described theoretically by a 2D Frenkel-Kontorova model. Upon including long-range elastic interactions, the stress-domain pattern is energetically favored. The surface topography and structure factor obtained by relaxing atomic coordinates using molecular dynamics bear a strong resemblance to scanning tunneling microscopy pictures and x-ray scattering data, respectively. Our numerical estimate for the separation between domain walls is consistent with experimental results.