A TOPOLOGICAL APPROACH TO THE STABILITIES OF ISOMERIC HUCKEL AND MOBIUS TYPE CYCLACENES

Within the constraints of Huckel molecular orbital theory, Huckel and Mobius type cyclacenes were investigated in terms of their angle of to tal pi-electron energy, O pi, and cos O pi to find out how structural changes affect the stabilities. It has been theoretically deduced that as the number of benzenoid rings (R) increases the isomeric Huckel an d Mobius type cyclacenes should have comparable stabilities, although for low values of R odd-Huckel type and even-Mobius type are predicted to be more stable.