First-principles molecular-dynamic relaxation was applied to the Si(111) surface in the 5 x 5 dimer–adatom–stacking-fault structure. The relaxed atomic surface geometry and the corresponding electronic structure were determined. It was found that the filled adatom dangling-bond states were segregated; with the charge density residing on the faulted side of the unit cell, and that the adatoms on the faulted side were higher than the adatoms on the unfaulted side. It was found that, at low temperatures, the adatoms on each side of the unit cell were corrugated into a variety of patterns.

Ab initio Molecular-Dynamical Relaxation Applied to the Silicon(111)-5 x 5 Surface Reconstruction. G.B.Adams, O.F.Sankey: Physical Review Letters, 1991, 67, 867-70