Electronic Properties of Silicene: Insights from First-Principles Modeling

The electronic properties of two dimensional hexagonal silicon (silicene) are investigated using first-principles simulations. Though silicene is predicted to be a gapless semiconductor due to the -hybridization of the Si atoms, the weak overlapping between their orbitals leads to a very reactive surface, resulting in a more energetically stable semiconducting surface upon the adsorption of foreign chemical species. It is predicted that silicene inserted into a graphitelike lattice, such as ultrathin AlN stacks, preserves its -hydridization and hence its graphenelike electronic properties.