Series of trinuclear [Ni.sup.II][Ln.sup.III][Ni.sup.II] complexes derived from 2,6-di(acetoacetyl)pyridine: Synthesis, structure, and magnetism

A series of trinuclear [Ni.sub.2.sup.II][Ln.sup.III] complexes of 2,6-di(acetoacetyl)pyridine ([H.sub.2]L) (Ln = La-Lu except for Pm) are synthesized by a 'one-pot reaction' of [H.sub.2]L, Ni[(N[O.sub.3]).sub.2].6[H.sub.2]O and Ln[(N[O.sub.3]).sub.3].n[H.sub.2]O in methanol and their structures and magnetic properties are characterized. The results have shown that the [Ni.sup.II]-[Ln.sup.III] interaction is weakly antiferromagnetic for Ln = Ce, Pr, and Nd and ferromagnetic for Ln = Gd, Tb, Dy, Ho and Er.