On the belt and moebius isomers of the coronene molecule

The structure and stability of ca. 100 nonplanar constitutional isomers of the coronene molecule of general formula C(24)H(12) have been estimated by semiempirical and by ab initio calculations. The isomers studied are unbranched cyclic catacondensed structures and fall into two classes, viz., the belt (B) and the Moebius (M) type. The calculations have shown some of the M-isomers to be more stable than the corresponding B-isomers and thus to form a platform for the future synthesis of or search for such isomers in Nature.