Ab initio calculations were made of the 2 x 1, c(2 x 8) and 7 x 7 reconstructions of the diamond, Si and Ge(111) surfaces. The π-bonded chain, adatom and dimer-adatom-stacking fault models were studied in order to understand the driving forces for a given reconstruction. The resultant energetics, geometries and band structures were compared for elemental semiconductors with various atomic sizes, and the chemical trends were deduced. It was shown why the lowest-energy reconstructions were different for these group-IV materials.

Origin of the Different Reconstructions of Diamond, Si, and Ge(111) Surfaces. F.Bechstedt, A.A.Stekolnikov, J.Furthmüller, P.Käckell: Physical Review Letters, 2001, 87[1], 016103 (4pp)

c(2 x 8) Reconstruction of Ge (111)