TiSi2-Nanostructures - Enhanced Conductivity at Nanoscale?

The stability, the structural and the electronic properties of elongated titanium silicide nanostructures have been investigated by density-functional-based tight-binding calculations. Our results show that the strain energy in tubular form does not follow the trends observed for other layered materials; tubes from TiSi2 are more stable than the flat monolayer, because in nanotubes free valences of Ti and Si atoms can be saturated for geometric reasons. Multi-layered tubes are energetically favoured and exhibit a tendency towards facetting. All such nanostructures are metallic with a density of Ti(3d) states at the Fermi level, which is considerably higher than that of the bulk compound. Thus, nanostructured TiSi2 may exhibit a better conductivity than the bulk phase along the tube direction.