Universal parameter tight-binding molecular dynamics: Application to C60

First-principles molecular-dynamics simulation is carried out for covalent systems with arbitrary (i.e., tetrahedral and nontetrahedral) coordination in a nonorthogonal, tight-binding basis, generalizing previous successful applications to tetrahedral solids. The generalized method is applied to study various aspects of the C60 molecule, including the effect of doping on vibrational modes, and interaction with heteroatoms. Considerable increase in the double-bond length and a much smaller increase in the single-bond length are found. Oxygen chemisorption occurs over the bridge site along the carbon-carbon double bond, weakening the latter