Two solvent-stable Dy2 compounds constructed by a large conjugated diacylhydrazone ligand: Disparate crystal structures and single-molecule-magnet behaviors

Abstract

Two new dinuclear Dy(III)-based compounds [Dy2(HL)2]·2CH3OH·CH3CN (1) and [Dy2(dbm)2(H2L)2]·6CH3CN (2) (H4L = N', N''-((1E,1′E)-(1,10-phenanthroline-2,9-diyl)bis(methaneylylidene))bis(2-hydroxybenzohydrazide), and Hdbm = dibenzoylmethane) constructed by a large conjugated diacylhydrazone ligand (H4L) have been successfully synthesized under solvothermal conditions. The crystal structures, fluorescent properties, and magnetic properties of the two Dy2 compounds (1 and 2) have been systematically studied. Compounds 1 and 2 show different molecule structures (Compound 1 displays a cattail leaf fan shape, while compound 2 displays a pinwheel-shapedcage). Both compounds 1 and 2 show well solvent stability. Moreover, magnetic properties study reveals that compounds 1 and 2 show single-molecule-magnet behaviors with different energy barrier (the anisotropic barriers (ΔE/kB) is 29.45 K for 1 and 62.52 K for 2. Compounds 1 and 2 show different magnetic properties due to the different chemical environments around the center Dy(III) ions.