SiC2 Silagraphene and Its One-Dimensional Derivatives: Where Planar Tetracoordinate Silicon Happens

The periodic systems containing planar tetracoordinate silicon (ptSi), SiC2 silagraphene, nanotubes, and nanoribbons, were predicted by means of density functional theory (DFT) computations. In SiC2 silagraphene, each silicon atom is bonded by four carbon atoms in a pure plane, representing the first anti-van't Hoff/Lebel species in the Si-containing extended system. SiC2 nanotubes, rolled up by the SiC2 silagraphene, exhibit excellent elastic properties. All these ptSi-containing nanomaterials are metallic, regardless of the chirality, tube diameter, or ribbon width. The high stabilities of these systems strongly suggest the feasibility for their experimental realizations.