C115: A coplanar double-C60-cage molecule with odd carbon atoms

Using geometry optimization and semiempirical AM1 and PM3 methods for C115, an equilibrium geometry is identified that has the form of a coplanar double-C60 cage. Vibrational frequencies and the infrared spectrum are computed at the same level of theory. The determined energy change for the reaction (115/60)C60=C115 and the heat of formation of C115 as well as the vibrational analysis indicates that this system enjoys sufficient stability to allow its experimental preparation