A study of the size-dependent elastic properties of silicon carbide nanotubes: First-principles calculations

The size dependence of elastic properties in single-walled silicon carbide nanotubes are investigated by first-principles calculations. We found the Young's modulus of the nanotubes increases with increasing diameter and is inversely proportional to Si-C bond length, whereas the Poisson ratio shows an opposite trend. For small tubes the elastic properties change dramatically with the tube size. While for the tubes with the diameter larger than 8 angstrom, the difference of these properties is small and almost independent of the size and symmetry. The strength of bonding between Si and C atoms is elucidated by the amount of the charge transfer calculated by the Bader analysis. (c) 2012 Elsevier B.V. All rights reserved.