Synthesis, characterization and properties of lanthanide complexes with different ancillary ligands

Abstract

By introducing different ancillary ligands and solvent molecules, four lanthanide complexes [Yb2(L)2(acac)2(CH3OH)2]·CH3OH·H2O (1), [Lu2(L)2(acac)2(CH3OH)2]·2CH3OH (2), [Yb2(L)2(dbm)2(CH3OH)2]·CH3OH (3), and [Lu2(L)2(dbm)2(C2H5OH)2] (4) (where H2L = 2-(hydroxyimino)-2-[(5-methyl-2-hydroxyphenyl)methylene]hydrazide, Hacac = acetylacetonate and Hdbm = 1,3-diphenyl-1,3-propanedione) have been synthesized and characterized. The X-ray structural analyses show that complexes 1 and 2 are isostructural in the Triclinic system, space group Pī, complex 3 crystallizes in Monoclinic system, space group P21/c, and complex 4 crystallizes in Orthorhombic system, space group Pbca. The metal ions in complexes 1–4 are all eight-coordinated and show a similar distorted triangular dodecahedron coordination geometry. The fluorescence properties of complexes 1–4 were also investigated. Complexes 1 and 3 showed characteristic emission peaks of Yb(III) ion, while complexes 2 and 4 exhibited emission peaks consistent with that of the ligand when they were excited at the same wavelength.