title: The studies of enhanced fluorescence in the two novel ternary rare-earth complex systems.
abstract: Two novel ternary rare-earth complexes SmL(5).L'.(ClO(4))(2).7H(2)O and EuL(5).L'.(ClO(4))(2).6H(2)O (the first ligand L = C(6)H(5)COCH(2)SOCH(2)COC(6)H(5), the second ligand L' = C(6)H(4)OHCOO(-)) were synthesized and characterized by element analysis, molar conductivity, coordination titration analysis, IR, TG-DSC, (1)HNMR and UV spectra. The detailed luminescence studies on the rare-earth complexes showed that the ternary rare-earth complexes presented stronger fluorescence intensities, longer lifetimes, and higher fluorescence quantum efficiencies than the binary rare-earth materials. After the introduction of the second ligand salicylic acid group, the relative emission intensities and fluorescence lifetimes of the ternary complexes LnL(5).L'.(ClO(4))(2).nH(2)O (Ln = Sm, Eu; n=7, 6) enhanced more obviously than the binary complexes LnL(5).(ClO(4))(3).2H(2)O. This indicated that the presence of both organic ligand bis(benzoylmethyl) sulfoxide and the second ligand salicylic acid could sensitize fluorescence intensities of rare-earth ions, and the introduction of salicylic acid group was a benefit for the fluorescence properties of the ternary rare-earth complexes. The fluorescence spectra, fluorescence lifetime and phosphorescence spectra were also discussed.
authors.affiliation: College of chemistry and chemical engineering, Inner Mongolia University, Hohhot 010021, People's Republic of China.
authors.forename: Xiao-Jun
authors.initials: XJ
authors.lastname: Sun
authors.forename: Wen-Xian
authors.initials: WX
authors.lastname: Li
authors.forename: Wen-Juan
authors.initials: WJ
authors.lastname: Chai
authors.forename: Tie
authors.initials: T
authors.lastname: Ren
authors.forename: Xiao-Yan
authors.initials: XY
authors.lastname: Shi
mesh_terms: D005453:Fluorescence; D008024:Ligands; D016014:Linear Models; D008674:Metals, Rare Earth / Q000737:chemistry*; D019906:Nuclear Magnetic Resonance, Biomolecular; D011522:Protons; D020156:Salicylic Acid / Q000737:chemistry; D012980:Sodium Salicylate / Q000737:chemistry; D013055:Spectrophotometry, Infrared; D013056:Spectrophotometry, Ultraviolet; D013057:Spectrum Analysis; D013696:Temperature
chemical_list: D008024:Ligands; D008674:Metals, Rare Earth; D011522:Protons; D020156:Salicylic Acid; D012980:Sodium Salicylate