Bi layers on the Mo(112) surface: A DFT study

Abstract

Relativistic DFT calculations performed for Bi layers adsorbed on the Mo(112) surface have shown that Bi atoms tend to occupy adsorption sites in furrows and, at a half-monolayer coverage, form a rectangular p(2 × 1) structure. For a complete Bi monolayer, the most preferred structure is the centered c(2 × 1) structure, with one half of Bi adatoms in on-row sites. No Bi-induced surface states have been indicated along Γ – X, corresponding to the direction along furrows, which can explain only minor changes in the band structure and density of states in vicinity of E_F with increasing Bi coverage. On the contrary, changes in the band structure along Γ – Y turn out to be very significant. Specifically, the SOC-splitting band, associated with surface states generated by the Bi adlayer, moves upward and twice crosses E_F thus becoming a valence band. This feature may be important in the search for new layered structures for nano and spin-electronics.