Electronic energy-band structures of covalent atomic and partly ion wires ANB8–N

The thinnest nanowires represent chains with one atom in cross section. The energy-band structures of A N B 8– N chains are calculated using the linear augmented cylindrical wave method. The energy-band structures of covalent monoatomic chains of the fourth group elements are characterized by the σ( s ), π + , and π – bands, as well as the σ( p z )* band. The chains of C, Si, Ge, and Sn are the metallic ones. Owing to the cylindrical symmetry of the chains, the spin and the orbital motion of electrons interact in the chains, splitting the π bands, but each π + - and π – band is doubly degenerate on the spin. The energy of spin–orbit splitting varies from 1.7 meV to 0.67 eV for the C and Sn chains, respectively.