Structure and energetics of Si(111)-(5x2)-Au

Abstract

We propose a new structural model for the Si(111)-(5x2)-Au reconstruction. The model incorporates a new experimental value of 0.6 monolayer for the coverage of gold atoms, equivalent to six gold atoms per 5x2 cell. Five main theoretical results, obtained from first-principles total-energy calculations, support the model. (1) In the presence of silicon adatoms the periodicity of the gold rows spontaneously doubles, in agreement with experiment. (2) The dependence of the surface energy on the adatom coverage indicates that a uniformly covered phase is unstable and will phase-separate into empty and covered regions, as observed experimentally. (3) Theoretical scanning tunneling microscopy images are in excellent agreement with experiment. (4) The calculated band structure is consistent with angle-resolved photoemission spectra; analysis of their correspondence allows the straightforward assignment of observed surface states to specific atoms. (5) The calculated activation barrier for diffusion of silicon adatoms along the row direction is in excellent agreement with the experimentally measured barrier.

11 pages, 7 figures, also available with higher-resolution figures from http://cst-www.nrl.navy.mil/users/erwin/ausi111.v5.pdf

References in corpus (6)

• Atomic Scale Memory at a Silicon Surface
• Self-Doping of Gold Chains on Silicon: A New Structural Model for Si(111)5x2-Au
• First-principles study of the atomic and electronic structure of the Si(111)-(5x2-Au surface reconstruction
• Stability and structure of atomic chains on Si(111)
• Stabilization of silicon honeycomb chains by trivalent adsorbates
• Phase transition at finite temperature in one dimension: Adsorbate ordering in Ba/Si(111)3x2

Cited by in corpus (4)

• Intrinsic magnetism at silicon surfaces
• Double Au rows on Si(553) surface
• Identification of the Au coverage and structure of the Au/Si(111)-5x2 surface
• Electron Quantization in Broken Atomic Wires