Spin polarization and dimer buckling at the Si(100)-2×1 surface

Abstract
A spin-resolved nonparametrized calculation of the electronic structure of the Si(100)-2×1 surface is presented. The current symmetric and asymmetric dimer models are considered. An energy gain of about 0.5 eV per surface atom is gained by including spin correlations in the calculations. The electronic charge and spin densities in the vicinity of the surface are presented. The results of the calculations strongly suggest that the dimer buckling is much smaller than predicted by previous spin-independent calculations.