Ferromagnetically coupled bis(semiquinone) ligand enforces high-spin ground states in bis-metal complexes

The pi -connectivity of a bis(semiquinone) ligand enforces ferromagnetic coupling between the two semiquinone halves of the molecule. Using the ligand in connection with paramagnetic metal ions lends to complexes with S = 3 (M = Ni-II), S = 2 (M = Cu-II), and S = 2 (M = Cr-III) ground states. [GRAPHICS]