Five new tri-spin lanthanide–nitronyl nitroxide (LnIII = GdIII, TbIII, DyIII, HoIII, ErIII) complexes: Structures and magnetic properties

Five radical–Ln(III)–radical complexes, [Ln(hfac)3(NITPhOC4H9)2] (Ln = Gd (1), Tb (2), Dy (3), Ho (4), Er (5); hfac = hexafluoroacetylacetonate; and NITPhOC4H9 = 4′-butoxy-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide) have been synthesized, structurally and magnetically characterized. The X-ray crystal structure analysis reveals that the structures of the five complexes are isomorphous in which central Ln(III) ions are coordinated by six oxygen atoms from three hfac and two oxygen atoms from nitronyl radicals. The magnetic studies show that in the Gd(III) complex, there are ferromagnetic Gd(III)–Rad interactions and antiferro-magnetic Rad–Rad interactions in the molecules (with JRad–Gd = 0.19 cm−1, JRad–Gd = −1.91 cm−1). And the analogous complex of [Tb(hfac)3(NITPhOC4H9)2] (2) shows the strong ferromagnetic Tb(III)–Rad interactions.