Comparison of electronic structure between monolayer silicenes on Ag (111)

The electronic structures of monolayer silicenes (4×4 and √13×√13R13.9^o) grown on Ag (111) surface are studied by scanning tunneling spectroscopy (STS) and density functional theory (DFT) calculations. While both phases have similar electronic structures around the Fermi level, significant differences are observed in the higher energy unoccupied states. The DFT calculations show that the contributions of Si 3p_z orbitals to the unoccupied states are different because of their different buckled configurations.