Stable NiII Porphyrin meso-Oxy Radical with a Quartet Ground State.

10,15,20-Tris(pentafluorophenyl)-substituted Ni^II-porphyrin meso-oxy radical bearing two coordinating pyridines was synthesized as a stable radical with a quartet ground state ( S=3/2). X-ray structural analysis revealed that the Ni^II porphyrin moiety is fairly planar and the Ni−N bond lengths are considerably longer, indicating the high-spin state of the Ni^II center. The radical exhibited a quartet ground state, indicating the ferromagnetic interaction between the high-spin Ni^II center ( S=1) and the porphyrin meso-oxy radical ( S=1/2). [ABSTRACT FROM AUTHOR]