Borazine embedded cyclacenes - a theoretical study

Semiempirical molecular orbital treatment at the level of an AM1 type has b een performed on the Huckel type borazine embedded cyclacenes having 3-10 a renoid rings. Although, the thermodynamic energies exhibit no cryptoannulen ic effect depending on the 4m or 4m + 2 nature of the peripheral circuits, the HOMO and LUMO energies, as well as the interfrontier molecular orbital gaps are affected by the cryptoannulenic effect. In general, the peripherie s have opposite charge accumulation leading to the arousal of a dipole mome nt originating from the nitrogen-rich periphery to the boron-rich periphery . (C) 2000 Elsevier Science B.V. All rights reserved.