Syntheses, crystal structures, magnetic and luminescent properties of lanthanide complexes with nitronyl nitroxide radical as ligand.

Four lanthanide-nitronyl nitroxide radical complexes, [Ln(hfac)3(NIT-3Methien)2] (Ln = Pr (1), Tb (2), Dy (3), Ho (4); hfac = hexafluoroacetylacetonate; NIT-3Methien = 2-(3-methylthiophene)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide), have been synthesized, and structurally and magnetically characterized. Single-crystal X-ray diffraction shows that1–4have similar mononuclear tri-spin structures in which central Ln(III) ions are eight coordinate by two NIT-3Methien radicals and three hfac coligands. The magnetic studies indicate that there are antiferromagnetic interactions between Ln(III) ions and radicals in1,2, and4, while ferromagnetic interactions are present in3. The luminescence properties of2and3were studied. [ABSTRACT FROM AUTHOR]