Dynamics of extensively reconstructed surfaces: Si(111) 2×1

We present a bond-charge-model, slab calculation of the 2×{}1 reconstructed Si(111) surface dynamics, which enlightens long-unexplained experimental features and provides general guidelines for the dynamical study of deeply reconstructed surfaces. This analysis is based on the concepts of geometrical folding in the surface Brillouin zone, reconstructed-to-ideal interface, and structural interpretation of the gaps that appear in the folded branches.