Trinuclear, octanuclear and decanuclear dysprosium(III) complexes: Synthesis, structural and magnetic studies

Three new polynuclear dysprosium complexes have been synthesized and characterized via X-ray crystallographic and magnetic measurements. The crystallographic data revealed tri-, octa- and deca-nuclear clusters of formulae [DyIII3(OH)(teaH2)3(paa)3](Cl)2·MeCN·4H2O (1), [DyIII8(OH)6(teaH)6(teaH2)2(teaH3)2](O3SCF3)4·0.5MeOH·2H2O (2) and [DyIII10O2(OH)6(o-van)6(ISO)13(H2O)2](NO3) (3) using the bridging ligands triethanolamine (teaH3), N-(2-pyridyl)-acetoacetamide (paaH), o-vanillin (o-van) and isonicotinic acid (ISO). Compound 1 displays a triangular metallic core, while compound 2 reveals three fused butterfly motifs. Compound 3 displays two trigonal-prismatic units, which are bridged via a single isonicotinate ligand. Variable temperature dc magnetic susceptibility measurements reveal an overall decrease in the χMT (χM = molar magnetic susceptibility) product upon lowering the temperature for 1, 2 and 3, with ac magnetic measurements for 2 and 3 displaying peak ‘tails’ in the out-of-phase susceptibilities (χM″) below 8 K, indicating single molecule magnet behavior.

Variation in reaction conditions and counter-anions in which dysprosium(III) salts are reacted with ligands such as triethanolamine (teaH3), N-(2-pyridyl)-acetoacetamide (paaH), o-vanillin (o-van) and isonicotinic acid (ISO), has led to isolation of new tri-, octa- and decanuclear clusters of formulae [DyIII3(OH)(teaH2)3(paa)3](Cl)2·MeCN·4H2O (1), [DyIII8(OH)6(teaH)6(teaH2)2(teaH3)2](O3SCF3)4·MeOH·2H2O (2) and [DyIII10O2(OH)6(o-van)6(ISO)13(H2O)2](NO3) (3). The structural and magnetic properties are described with single molecule magnetism (SMM) features being displayed by 2 and 3, but not, surprisingly, by the triangular complex 1.Figure optionsDownload as PowerPoint slide