Syntheses, structural modulation, and slow magnetic relaxation of three dysprosium(III) complexes with mononuclear, dinuclear, and one-dimensional structures

Three mononuclear, dinuclear and one-dimensional dysprosium(m) complexes based on 3-azotriazolyl-2,6-dihydroxybenzoic acid (H(4)ATB) of [Dy(H(3)ATB)(3)]center dot 3H(2)O (1), [Dy-2(HpATB)(2)(H2DHB)(2) (H2O)(4)]center dot 2CH(3)CN center dot 5H(2)O (2), and [Dy-2(H(2)ATB)(2)(DCB)(DMF)(2)(H2O)(2)]center dot 4DMF (3) were synthesized and structurally characterized by X-ray single crystal diffraction (H3DHB = 2,6-dihydroxybenzoic acid, H2DCB = 1,4-dicarboxybenzene). Complex 1 was used as a precursor to synthesize complexes 2 and 3, and 2 was further used to synthesize 3. Complex 1 is a mononuclear complex, in which the Dy(iii) ion is in a nine-coordinated structure surrounded by three tridentate chelate H(3)ATB(-) ligands. Complex 2 displays a dinuclear structure bridged by two mu(2) carboxyl groups of two H(2)DHI3(-) ligands and two mu(1.1)-O atoms from the phenolic hydroxyl groups of two H(2)ATI3(2-) ligands. Complex 3 shows a one-dimensional structure formed by two bridging DCB2- ligands. The magnetic measurements were performed on three complexes 1-3, and they showed different magnetic behavior. Complex 1 shows a field-induced slow magnetic relaxation. Complexes 2 and 3 display distinct slow magnetic relaxation under zero dc field with energy barriers (U-eff) of 26(2) cm(-1) and 11(1) cm(-1), respectively. The magnetic behavior of three complexes 1-3 was investigated by ab initio calculations.

Automated summary

Three novel dysprosium complexes based on 3-azotriazolyl-2,6-dihydroxybenzoic acid were synthesized and structurally characterized by X-ray crystallography, showing mononuclear, dinuclear, and one-dimensional structures. Magnetic measurements revealed diverse magnetic behaviors in the complexes, including slow magnetic relaxation and energy barriers. Ab initio calculations were also conducted to investigate the magnetic behavior of the complexes.