Properties Of Rare-Earth Complexes With 8-Hydroxyquinoline Derivatives And ?-Diketones Ligands

In the past few decades, design and synthesis of complexes with rare-earth metals and organic ligands have been extensively studied for diverse topologies, aesthetic beauty, and potential applications in gas storage and separation, which allows for promising applications in functional materials such as catalysis, magnetism, chemical sensors, and luminescence. The rare-earth metal complexes with 8-hydroxyquinoline derivatives and ?-diketones which not only has the feature of high luminous efficiency, but also may be single molecule magnets (SMMs) or good magnetic materials.The thesis applied four different 8-hydroxyquinoline derivatives as ligands. Eight new complexes based on 8-hydroxyquinoline derivatives and P-diketones as ligands, [Gd4(acac)4(C9H5N2O3)6(?-OH)2] (1), [Dy4(acac)4(C9H5N2O3)6(?-OH)2](2), [Ho3(hfac)9(C9H7N2O)2(H2O)2]-1.5H2O (3), [Eu(hfac)3(C9H7N2O)] (4), [Pr4(hfac)12(C16H11N2O2)4]·C7H16 (5), [Gd2(hfac)6(C16H11N2O2)2]·C7H16 (6), [Tb4(acac)4(C16H11N2O)6(?3-OH)2]·3CH3OH·H2O (7) and [Gd4(acac)4((C16H11N2O)6(?3-OH)2]·3CH3OH·H2O (8) have been obtained by adjusting the reaction conditions and changing the ?-diketones ligands. The complexes characterized by X-ray single crystal diffraction, TG, X-ray power diffraction. The magnetic properties of complexes 1,2,7 and 8 have been investigated.Complexes 1 and 2 are isostructural and they are crystallized in the triclinic, space group P1. They were designed and synthesized in the same condition. Both of complexes 1 and 2 are pantanuclear structure. Magnetic properties indicate that complex 2 exhibits single molecule magnet behavior. The energy barrier AE/kB is 89.31 K which was obtained by fitting using Arrhenius formula. The pre-exponential factor is ?o= 8.4 × 10-8 s. Complex 3 and complex 4 are trinuclear and mononuclear respectively based on 5-amino-8-hydroxyquinoline. Complex 5 and 6 were obtained by refiuxing the solvents under 102?. In complex 7, the metal ions show weak ferromagnetic interactions.