JOURNAL OF PORPHYRINS AND PHTHALOCYANINES, vol.3, no.4, pp.259-264, 1999 (SCI-Expanded)
An AM1-type semiempirical molecular orbital treatment has been performed on certain [2(2)]-type cyclophane-fused tetraazaporphyrins. It has been found that within the isomeric set of structures the most and the least endothermic porphyrins are the ones having non-Hamiltonian and Hamiltonian cyclophane moieties respectively. On the other hand, the lowest HOMO and LUMO and the highest HOMO energies are possessed by the structures bearing Hamiltonian and non-Hamiltonian cyclophane moieties respectively, whereas the highest LUMO energy belongs to a Hamiltonian cyclophane-fused system within the same type of isomeric structures. Copyright (C) 1999 John Wiley & Sons, Ltd.