Rigid crystalline phases of polymerized fullerenes

Combining total energy and structure optimization calculations, we explored new possible crystalline phases of covalently bonded C60 fullerenes and determined their structural, elastic, and electronic properties. Motivated by reported observations that bulk structures of polymerized fullerenes may be stiffer than diamond, we have explored possible ways of fullerene polymerization and have identified 12 stable crystal structures as potential candidates. Even though all these phases are very stiff, none of them exceeds the bulk modulus of diamond. The electronic structure of three-dimensional crystals of polymerized C60 depends mainly on the packing structure of the system, with only minor modifications due to the specific inter-fullerene bonding.