A characteristic dimer buckling pattern was observed around a missing-dimer defect on the (100) surface, near to the critical temperature, by using low-temperature scanning tunnelling microscopy. The dynamic properties of this surface were studied by applying a Monte Carlo technique to an Ising system, in which the buckled dimers were regarded as being Ising spins. The interaction parameters were determined by using ab initio calculations within the local density approximation. It was found that the simulated scanning tunnelling microscopic images were in good agreement with observed images over the whole temperature range.

Strain Effects of Missing Dimer Defects on Dimer Buckling of the Si(100) Surface. M.Okamoto, T.Yokoyama, T.Uda, K.Takayanagi: Physical Review B, 2000, 62[19], 12927-31