The Ga- and As-terminated GaAs(100) surfaces were studied via first-principles density-functional pseudopotential calculations of the energies of surfaces with different stoichiometries and reconstructions. Structural transitions were predicted as a function of Ga and As chemical potentials within an experimentally accessible range which was shown to be fixed by the bulk energies of Ga, As, and GaAs. The bulk energies were determined accurately by the ab initio calculations. The predicted surface stoichiometries were in good agreement with experimental data.

Stoichiometry and Surface Reconstruction - an ab initio Study of GaAs(100) Surfaces. G.X.Qian, R.M.Martin: D.J.Chadi: Physical Review Letters, 1988, 60, 1962-5