The reconstruction of the As-terminated GaAs(100) surface was examined using both the tight-binding and the self-consistent pseudopotential methods. Dimer models with unit cells as large as the one seen in electron-diffraction experiments were tested. Unlike the Si(100) surface, symmetric as well as asymmetric dimers were predicted to occur in equal densities at the surface.

Theoretical Study of the As(100) Surface Reconstruction of GaAs. D.J.Chadi, J.Ihm, C.Tanner, J.D.Joannopoulos: Physica B+C, 1983, 117-118[2], 798-800