Bond Distortions in Armchair Type Single Wall Carbon Nanotubes
  The energy band gap structure and stability of (3,3) and (10,10) nanotubes have been comparatively investigated in the frameworks of the traditional form of the Su-Schrieffer-Heeger (SSH) model and a toy model including the contributions of bonds of different types to the SSH Hamiltonian differently. Both models give the same energy band gap structure but bond length distortions in different characters for the nanotubes. 
N. Sunel, E. Rizaoglu, K. Harigaya, and O. Ozsoy