Atomic and electronic structure of theK∕Si(111)3×3R30°−Bchemisorption system

Abstract

Ab initio plane-wave pseudopotential density functional theory (DFT) calculations have been carried out to determine the atomic and electronic structure of the K/Sis111dI33I3R30°-B adsorption system at 1 /3 monolayer coverage. Chemisorption of the potassium atoms has been found to leave the topology and bonding structure of the Sis111dI33I3R30°-B substrate essentially unchanged. The results also show that the lowestenergy K/Sis111dI33I3R30°-B structures are very similar to the most energetically favorable geometries for the K/Sis111d737 chemisorption system. The minimum energy configuration has been found to be a structure in which the potassium atoms are positioned near the hollow H3 sites, the boron atoms occupy the subsurface S5 positions, and the silicon adatoms are located at the T4 sites. The electronic structure of this lowest-energy K/Sis111dI33I3R30°-B configuration has been found to be metallic.