An investigation was made of various surface reconstructions of a GaAs(311)A surface by using first-principles calculations. The relative stability of the reconstructions was compared by estimating the formation energies; taking into account the chemical potentials of Ga and As. It was found that the most stable reconstruction of the (311)A surface did not satisfy the electron counting model, although the electron counting model was a strong guiding principle for determining stable surface reconstructions of GaAs(100), (111)A and (110) surfaces. Further investigations indicate that the sp2-like-bond formation effectively works at the (311)A surface. Competition between sp2-like-bond formation and As-dimer formation would explain why the electron counting model was not so effective at this surface.

First-Principles Investigations of GaAs(311)A Surface Reconstruction - Failure of the Electron Counting Model. A.Taguchi, K.Shiraishi: Applied Surface Science, 2004, 237[1-4], 189-93