Three Ln2 compounds (Gd2, Tb2 and Dy2) with a Ln2O2 center showing magnetic refrigeration property and single-molecular magnet behavior

Abstract

Three dinuclear Ln2 compounds, [Ln2(dbm)4(L-)2]·4CH3CN (Ln = Gd (1), Tb (2), Dy (3), HL = (E)-N'-(2-hydroxybenzylidene)benzohydrazide and dbm = dibenzoylmethane), have been obtained by a solvent evaporation method. The structural analyses indicate that the three Ln2 compounds (Gd2, Tb2 and Dy2) are isostructural with a Ln2O2 center. Magnetic investigations show the presence of magnetic refrigeration in the Gd-based compound with a -ΔSm value of 17.62 J kg−1 K−1 (T = 2.0 K and ΔH = 7.0 T); for compound 3, however, single-molecular magnet behavior (SMM) was observed (Ueff /kB = 0.84 K and τ0 = 1.08 × 10−5 s).