We have investigated structural and electronic properties of the B80 buckyball and boron nanotubes by means of dispersion-corrected density-functional calculations. Our analysis reveals the vibrational stability for the icosahedral B80 with the inclusion of dispersion corrections, in contrast to the instability to a tetrahedral B80 with puckered capping atoms from preceding density-functional theory calculations. Similarly, the dispersion-corrected density-functional calculations yield non-puckered boron nanotube conformations and an associated metallic state for zigzag tubes. Our study indicates that the incorporation of long-range dispersive interactions is particularly important to the structural and electronic properties of boron fullerenes and nanotubes.

We have revisited the general constructing schemes for a large family of stable hollow boron fullerenes with 80 + 8n (n = 0, 2, 3, ...) atoms. In contrast to the hollow pentagon boron fullerenes with 12 hollow pentagons, the stable boron fullerenes constitute 12 filled pentagons and 12 additional hollow hexagons, which are more stable than the empty pentagon boron fullerenes including the "magic" B80 buckyball. On the basis of results from first-principles density-functional calculations, an empirical rule for filled pentagons is proposed along with a revised electron counting scheme to account for the improved stability and the associated electronic bonding feature.

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