In nanolines and nanoclusters on self-assembled Bi-lines

We have performed an ab initio total energy investigation of In nanolines and nanoclusters adsorbed along self-assembled Bi-lines on the hydrogenated Si(0 0 1) surface. The calculations were performed within the density functional theory, using pseudopotentials to describe the electron–ion interactions. We have examined several metastable In atomic arrangements “around” the Bi-lines. Our total energy results indicate that the In segregation towards the Bi-line is an energetically favorable process. We find that the energetically most favorable of the metastable structures results from small clusters of In adatoms between the Bi-lines. The equilibrium geometry of this In nanocluster has been detailed, and it is found that covalent bonds are formed between the In cluster and the Bi atoms.