EXTENDED HUCKEL MOLECULAR-ORBITAL MODEL FOR LANTHANIDE BISPHTHALOCYANINE COMPLEXES

The electronic structure of lanthanide bisphthalocyanines (LnPc(2)) is examined using the frontier molecular orbitals of the phthalocyanine (Pc) ligand fragment in the framework of the extended Huckel Hamiltoni an. Correlation diagrams are constructed for a staggered conformation. It was found that the major component in the splitting of the energy levels was the ring-ring interaction. The largest splitting was calcul ated for the a(1u) HOMOs of the two rings. Molecular geometry-electron ic structure relationships are constructed using perturbation theory a nd overlap integrals.