Molecular orbital studies on the rings composed of D2d C36 cages

The structures and electronic properties of the rings composed of D2d C36 cages are investigated using the semi-empirical AM1 molecular orbital method with full geometric optimization. It is found that most of the converged structures are more stable after the rings are formed. Strain plays an important role in the stability of the fullerene rings. Other factors influencing the stability are also discussed, such as the type of the bonded carbon atoms and the size of retained aromatic domains. Comparison of the structures and electronic properties are made between the C36-rings and those composed of D6h C36 isomers.