Structure and stability of the Si(331)-(12×1) surface reconstruction investigated with first-principles density functional theory

We recently proposed a structural model for the Si (331) - (12×1) surface reconstruction containing silicon pentamers and adatoms as elementary structural building blocks. Using first-principles density functional theory we here investigate the stability of a variety of adatom configurations and determine the lowest-energy configuration. We also present a detailed comparison of the energetics between our model for Si (331) - (12×1) and the adatom-tetramer-interstitial model for Si (110) - (16×2), which shares the same structural building blocks.