Investigation of magneto-structural relation based on a series of mononuclear dysprosium single-ion magnets with high Oh symmetry

Abstract

Two mononuclear Dy(III) complexes [Dy(HL)2(CH3OH)Cl3] (1) and [Dy(L)2(CH3CH2OH)Cl3] (2) were obtained by organic ligand 5,7-dibromo-2-methyl-8-quinolinol (HL) with DyCl3·6H2O. Structure analysis suggested that the Dy(III) center in those two complexes had six octahedral coordinative configurations, but the symmetry of complex 2 (1.251) was obviously higher than that of complex 1 (1.419). The coordinated solvent molecule contributes significantly on the geometry of Dy(III) ions in the two diverse complexes. And magnetic investigations showed that complex 1 exhibited a weak field-induced single-molecule magnetic (SIM) behavior, but complex 2 showed obvious SIM behavior. For complex 2, the energy barriers were 36.8 (1) K and 50.8 (9) K, respectively. They are typical SMM examples with rare six coordination of Dy(III) ions.