Single-Molecule Magnet Behavior in a Tb-Nitronyl Nitroxide Radical Network with [Tb(NIT)] Nodes.

Two rare two-dimensional Ln-radical networks, namely, [{Ln(tfa)}(NIT-4Py)] [Ln = Gd and Tb ; tfa = trifluoroacetylacetonato; and NIT-4Py = 2-(4-pyridyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide], have been successfully constructed and characterized. In these complexes, each NIT-4Py radical functions as a tridentate ligand to ligate three Ln ions, creating a 2D network with linear five-spin [Ln(NIT)] nodes. Ferromagnetic Ln-NO interactions govern the characteristic magnetic behavior of a finite spin system. The Tb complex is shown to exhibit SMM behavior in a zero DC field, with an energy barrier for spin flipping of 53 K and hysteretic M-H behavior at 2.3 K, with a coercive field = 110 Oe. This complex represents the first example of a Ln-nitronyl nitroxide SMM-based network.