Structural stability of silicene-like nanotubes

Silicene-like (4,0)(4,0) zigzag metal-doped MnSi8(n+1)MnSi8(n+1) nanotubes are investigated by first-principles calculations. We show that the geometrical structures of silicon nanotubes can be stabilized by doping metal (K, Ca, Y and Lu). Electronic structure calculations show that Y and Lu atoms gain extra charge from Si atoms, the bonding between Si and the MnSi8(n+1)MnSi8(n+1) (M = K, Ca) is of a mixed metallic–covalent nature, and the magnetic moment of K14Si120 quenches completely compared with K7Si64. Some properties are discussed to provide guidance to experimental efforts for nanomagnetic materials and spintronics.

► We study novel finite metal endohedral silicene-like silicon nanotubes by density functional theory.
► Their structural stability increases along with the tube length increasing.
► The bonding between Si and the MnSi8(n+1)MnSi8(n+1) (M = K, Ca) is of a mixed metallic–covalent nature.
► The magnetic moment of K14Si120 quenches completely compared with K7Si64.