High-symmetry low-energy structures of C₆₀H₆₀ and related fullerenes and nanotubes

The structure, symmetry, and stability of C₆₀H₆₀ are studied by ab initio density functional theory and second order Møller-Plesset perturbation theory. It is shown that the lowest energy high symmetry (D_5d) cage of C₆₀H₆₀ is obtained by “puckering” of the H-C-C-H bonds through the endohydral bonding of ten C-H pairs of the full icosahedral fullerene. Such puckering can also lead to alternative D_5d symmetric structures and to other partially hydrogenated fullerenes which have been already synthesized as well as to single wall carbon nanotubes. The infrared spectrum of the proposed structure(s) is compatible with analogous astronomical data on the basis of which the existence of C₆₀H₆₀ in stellar atmospheres was postulated.