Two intact C60 cages linked by six carbon-carbon single bonds

The structures of two possible C60 dimers with two intact C60 cages linked by six carbon-carbon single bonds have been optimized by using the DFT method at the B3LYP/6-31G∗ level of theory. The two isomers of C60 dimers all have three cages, two C60 cages and one hexaprism cage. Symmetries of the two isomers are D3d and D3h, respectively. Vibrational frequencies of the two isomers are computed by using the PM3 method. The dimerization reaction to form the two C60 dimers from the C60 is calculated to be endothermic. While the pathways for decomposition to C60 are forbidden by orbital symmetry, thus it is possible that they can be observed experimentally as metastable molecules.