Neutral dicyanidoferrate(II) metalloligands for the rational design of dysprosium(III) single-molecule magnets.

Diamagnetic cis -dicyanidoferrate(II) complexes bearing blocking aromatic diimines, cis -[Fe II (CN) 2 (L NN ) 2 ] 0 (L NN = 2,2'-bipyridine, 1,10'-phenanthroline) serve as metalloligands to Dy III centres leading to a rigid cyanido-bridged chain of vertex-sharing {Dy III 2 Fe II 2 } squares which constrains the equatorial plane of embedded 4f metal ions. This results in a novel convenient route to rationally designed single-molecule magnets as the magnetic anisotropy of Dy III centres can be efficiently generated by inserting aromatic N -oxide ligands on labile axial positions.