Silicene on hydrogen-passivated Si(111) and Ge(111) substrates.

By means of first-principles calculations we predict the stability of silicene as buckled honeycomb lattice on passivated substrates of group-IV(111)1 × 1 surfaces. The weak van-der-Waals interaction between silicene and substrates does not destroy its linear bands forming Dirac cones at the Brillouin zone corners. Only very small fundamental gaps are opened around the Fermi level. [ABSTRACT FROM AUTHOR]