• Title/Summary/Keyword: lanthanide

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Retention Behavior of Lanthanide Complexes with $\alpha$ -hydroxyisobutyric Acid on Cation Exchanger (양이온 교환체에서 희토류원소와 $\alpha$-Hydroxyisobutyric Acid 착물들의 머무름 거동에 관한 연구)

  • Jo, Gi Su;Han, Seon Ho;Seo, Mu Yeol;Eom, Tae Yun;Kim, Yeon Du
    • Journal of the Korean Chemical Society
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    • v.34 no.6
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    • pp.582-592
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    • 1990
  • Retention behavior of lanthanide-$\alpha$HiBA complexes was studied on the cation exchanger (LC-18 coated with $C_{20}H_{41}SO_4^-$). An equation predicting retention of lanthanides in isocratic or gradient elution with sodium ion and $\alpha$-HiBA concentration was derived from ion exchange equilibria of metal-ligand complex system, respectively. The relations between log k' and log [Na$^+$] /log [$\alpha$-HiBA) showed non-linearity in isocratic elution. In gradient elution a good linearity between log k' vs log R was obtained. The values of slopes (log k / log R) gave good agreements between calculation and experiment. Individual capacity factors ($k'_{Ln}^{3+}, k'_{LnL}^{2+}, k'{LnL2+}) and stability constant (${\beta}_1$, ${\beta}_2$, ${\beta}_3$) of lanthanide-$\alpha$HiBA complexes were calculated by the non-linear least square fittings using the retention equation. The correlation coefficients of lanthanides were shown better than 0.9996 between experiment and calculation.

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A Series of 3D Lanthanide Complexes Containing (La(III), Sm(III) and Gd(III)) Metal-organic Frameworks: Synthesis, Structure, Characterization and Their Luminescent Properties

  • Zhang, Huai-Min;Yang, Hao;Wu, Lan-Zhi;Song, Shuang;Yang, Li-Rong
    • Bulletin of the Korean Chemical Society
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    • v.33 no.11
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    • pp.3777-3787
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    • 2012
  • Three kinds of 3D isomorphous and isostructural coordination polymers, namely, $\{[Ln_2(PDA)_3(H_2O)_3]{\cdot}0.25H_2O\}_{\infty}$ (Ln = La(1), Sm(2), and Gd(3)) ($PDA^{2-}$ = pyridine-2,6-dicarboxylate anion) have been synthesized under hydrothermal conditions and characterized by elemental analyses, IR spectroscopy, thermal analyses and single crystal X-ray diffraction. In these MOFs, Ln(III) centers adopt eight-coordinated and nine-coordinated with the $N_1O_7$ and $N_2O_7$ donor sets to construct distorted trianglar dodecahedron geometry and tricapped trigonal prism configurations, respectively. Based on the building block of tetranuclear homometallic $Ln_4C_4O_8$ unit (16-membered ring), 1-3 are connected into highly ordered 2D sheets via O-C-O linkers and further constructed into 3D architectures through hydrogen bonds. Crystallographic parameters suggest that the lanthanide contraction effect exist in these coordination polymers. Luminescent properties of the lanthanide-based MOFs (metal-organic frameworks) have been measured at room temperature, which reveal that they presenting ionselective characters toward certain metals, such as $Mg^{2+}$, $Cd^{2+}$ and $Pb^{2+}$ ions.

Lanthanide Complexes of Some High Energetic Compounds (II), Crystal Structures and Thermal Properties of Picrate Complexes

  • Yun, Sock-Sung;Kang, Sung-Kwon;Suh, Hong-Ryol;Suh, Hyung-Sock;Lee, Eun-Kwang;Kim, Jae-Kyung;Kim, Chong-Hyeak
    • Bulletin of the Korean Chemical Society
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    • v.26 no.8
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    • pp.1197-1202
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    • 2005
  • The Ln(III) complexes with picrate ligand, $[Sm(Pic)_2(H_2O)_6]Pic{\cdot}6H_2O$, 1, and $[Ho(Pic)(H_2O)_7](Pic)_2{\cdot}3H_2O$, 2, have been synthesized and their crystal structures are analyzed by X-ray diffraction methods. Complex 1, crystallizes in the monoclinic $P2_1/n$ space group and complex 2 in the triclinic P-1 space group. In complex 1, two picrate ligands coordinate to the Sm(III) ion, one of them in the bidentate fashion. There are one picrate anion and six water molecules in the crystal lattice. The nine-coordinated Sm(III) ion forms a slightly distorted tricapped trigonal prism. In complex 2, only one picrate ligand coordinates to the metal ion as a monodentate. There are two picrate anions and three water molecules in the crystal lattice. The eight-coordinated Ho(III) ion forms a distorted bicapped trigonal prism. Based on the results of the TG-DTG and DSC thermal analysis, it was analyzed that the lanthanide picrate complexes 1 and 2 are thermally decomposed in three distinctive stages, the dehydration, the picrate decomposition, and the formation of the metal oxide.

Electrochemical Behavior of Light Lanthanide Ions in Nonaqueous Solution, Flow Injection Determination and Photochemical Characterization of Eight Coordinated Chelates of Heavy Metal Ions (Part I) Electrochemical Behavior of Light Lanthanide Ions in Nonaqueous Solution (물아닌용매에서 가벼운 란탄족 이온의 전기화학적 거동, 흐름주입에 의한 정량 및 중금속이온의 킬레이트형 8-배위 착물의 광화학적 특성 (제 1 보) 물아닌용매에서 가벼운 란탄족이온의 전기화학적 거동)

  • Kang, Sam-Woo;Pak, Chong-Min;Do, Lee-Mi;Song, Myoung-Kyu;Kim, Il-Kwang
    • Analytical Science and Technology
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    • v.7 no.3
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    • pp.361-369
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    • 1994
  • Voltammetric behavior of some light lanthanide ions($La^{3+}$, $Pr^{3+}$, $Nd^{3+}$, $Sm^{3+}$ and $Eu^{3+}$) in acetonitrile(AN) and dimethylformamide(DMF) has been investigated by direct current, differential pulse polarography and cyclic voltammetry. The reduction of $La^{3+}$, $Pr^{3+}$ and $Nd^{3+}$ in 0.1M TEAP proceeded directly to the metallic state through three-electron charge transfer of irreversible process where as $Sm^{3+}$ and $Eu^{3+}$ proceeded by charge transfer of two steps. As the results of the cyclic voltammetric investigation, the first step reduction of $Sm^{3+}$ and $Eu^{3+}$ were a quasireversible reaction, the second step reductions were an irreversible reaction. The cathodic peak currents of the differential pulse polarogram showed adsorptive properties at lower sweep rates and high concentrations of these metal ions. The peak potenital was shifted to a negative petential and the peak current decreased with the increase of percentage of water in AN. On the other hand, the peak potential was shifted to a positive potential and the peak current decreased with an increased percentage of water in DMF.

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