Abstract
Intrinsic surface electronic energy states for the ideal (1 × 1), relaxed (1 × 1), and reconstructed (2 × 1) Si(111) surfaces have been successfully calculated by use of the self-consistent scattered-wave cluster model. For both ideal and relaxed structures, we find three bands of surface states. For (2 × 1) reconstruction our dangling-bond surface band splits into two overlapping bands. Our results account for all the observed features in photoemission experiments on Si(111) surfaces.