state and an open-shell "Cu(II)" state, although they always use careful language to emphasize that these are indeed multiconfigurational singlets. The open-shell state was reported to be stabilized by a σ -π orbital interaction between the corrole π b 1 and the copper d x 2 -y 2 orbitals. On the planar structure, the "Cu(III)" 1 A closed-shell singlet is predicted to be the ground state, while both the open-shell 1 A "Cu(II)" singlet state and the triplet state are higher in energy. On the other hand, for the saddled geometry, the "Cu(III)" closed-shell singlet is significantly higher in energy, while the lower energy singlet is assigned to be "Cu(II)".