吡啶—2,6—二羧酸体系导数荧光法同时测定铀,钐,铕,铽,镝

本研究了吡啶－２，６－二羧酸（ＤＰＡ）体系导数荧光法同时测定铀，钐，铕，铽，镝的最佳条件。在ｐＨ５．５，４．８×１０＾－＾５ｍｏｌ／ＬＤＰＡ，激发波长２７２ｎｍ的条件下，可分别在５１８，６３９，６２１，５３９和６６ｎｍ处测定铀，钐，铕，铽和镝，检测限分别达到７，０．４，０．００４，０．０２６和０．２５ｎｇ／ｍＬ。应用本法测定了混合成试液中上术五种离子含量，回收率为９２．３－１０８．１％。     

Reactions of neodymium(ii), dysprosium(ii), and thulium(ii) diiodides with cyclopentadiene. Molecular structures of complexes CpTmI2(THF)3 and [NdI2(THF)5]+[NdI4(THF)2]–

The reactions of LnI₂ (Ln = Nd (1) or Dy (2)) with cyclopentadiene (CpH) in THF at 0 °C afforded the CpLnI₂(THF)₃ complexes in 65—67% yields. The reaction of thulium diiodide (3) with an excess of CpH at 60 °C produced CpTmI₂(THF)₃, Cp₂TmI(THF)₂, and TmI₃(THF)₃ in 21, 58, and 63% yields, respectively. The reactions of 1 and 2 with pentamethylcyclopentadiene (Cp*H) in THF were accompanied by disproportionation giving rise to the Cp*₂LnI(THF)₂ and LnI₃(THF) _x complexes. Neodymium triiodide was isolated in the ionic form [NdI₂(THF)₅]⁺[NdI₄(THF)₂]^–. Its structure and the structure of CpTmI₂(THF)₃ were established by X-ray diffraction analysis.     

YPxV1—xO4（0≤x≤1）：Dy^3＋的合成及其光谱性质的研究

本文报道了不同组成的ＹＰｘＶ１－ｘＯ４（０≤ｘ≤１）：Ｄｙ＾３＋的合成和结构。ＹＰｘＶ１－ｘＯ４（０≤ｘ≤１）为四方晶系，晶胞参数随ｘ的增大呈线性减小。基质的Ｓｔｏｋｅｓ位移随ｘ的增大逐渐变大，而激发光谱峰值则向短波方向移动。在ＹＰｘＶ１－ｘＯ４：０．００６Ｄｙ＾３＋体系中，ｘ＞０．４时出现的基质发射是由ＰＯ＾３－４引起的。基质及Ｄｙ＾３＋的发光效率和Ｄｙ＾３＋的发光强度的黄蓝比均与ｘ有关。同时探     

1,9—双（1′—苯基—3′—甲基—5′—氧代吡唑—4′—基）壬二酮—（1,9）与三？…

研究了１，９－双（１′－苯基－３′－甲基－５′－氧代吡唑－４′－基）壬二酮－（１，９）（ＢＰＭＰＮＤ，Ｈ２Ａ）与三辛基氧膦（ＴＯＰＯ，Ｂ）的氯仿溶液，从硝酸介质中对Ｌａ（Ⅲ），Ｄｙ（Ⅲ）的协同萃取，计算了体系的酸性协萃系数ＲＡ和协萃系数Ｒ，用斜率法测得协萃合物的组成ＬａＡ．ＨＡ．Ｂ和ＤｙＡ．ＨＡ．Ｂ计算了协萃取平衡常数，研究了温度对协萃反应的影响，用萃取法制得了固态协萃合物，并对其组成，ＩＲ及ＴＧ     

Complex lanthanide chromate(VI)-phosphates K2R(CrO4)(PO4) (R = Dy-Lu, Y)

The conditions of formation of complex lanthanide chromate(VI)-phosphates K₂R(CrO₄)(PO₄) were found and these compounds were synthesized by solid-state synthesis with variation of the starting compounds, the temperature of synthesis (500–800 °C), and the annealing time (6–200 h). These salts are typical of late lanthanides, R = Dy-Lu, Y. Using lutetium derivatives as examples, it was shown that no similar compounds with lithium or sodium are formed. All the complex chromate(VI)-phosphates obtained decompose under static conditions at temperatures above 550 °C. They are isostructural and crystallize in the monoclinic system. The unit cell parameters for thulium, ytterbium, and lutetium compounds were calculated. It is shown by IR spectroscopy that PO₄ tetrahedra in the crystal lattice of potassium lanthanide chromate(VI)-phosphates are substantially distorted, whereas the CrO₄ tetrahedra retain the regular tetrahedron symmetry (T _d ). Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 622–626, April, 2006.     

Determination of the apparent standard potential of the Dy/Dy(Ⅲ) system in the LiCl-KCl eutectic

The apparent standard potential of Dy/Dy(III) system in the LiCl-KCl eutectic has been determined by the logarithmic analysis of the semi-integrals of voltammograms, logarithmic analysis of chronopotentiograms and the open circuit potentiometry. The dysprosium equilibrium potentiab for various concentration of dysprosium chloride in the LiCl-KCl eutectic melt between 400-500℃ were first determined experimentally, and the apparent standard potential of this system and its temperature dependance have been calculated.     

DySBr und DySI – Synthese,Kristallstruktur und Magnetismus

DySBr and DySI – Synthesis, Crystal Structure, and Magnetism By reaction of Dy₂S₃ with Dy metal and Br₂ (I₂) at 750°C (900°C), single phase crystalline DySBr (DySI) has been synthesized. Crystal structure refinement of DySBr confirms the FeOCl-type structure (R = 0.049; space group Pmmn, Z = 2, lattice parameters (in Å): a = 5.349(2), b = 4.079(2), c = 8.066(2)) which is also ascertained for DySI (R = 0.059; lattice parameters (in Å): a = 5.320(2), b = 4.168(1), c = 9.224(5)). The magnetic susceptibilities (temperature range 3.4 K – 295 K) can be described on the basis of simple models (cubic crystal field, molecular field approximation) above 5 K and 15 K respectively. The deviations at low temperature are assumed to be related essentially to Dy—Dy exchange interactions which are not adequately described with the molecular field approach.     

Steric structure and thermodynamic aspects of the complexes of dysprosium(iii) with aminobenzoic acids in aqueous solutions

Steric structures of dysprosium(III) aminobenzoate complexes with the 11 and 12 molar ratio in aqueous solutions were determined on the basis of pH-metric and paramagnetic birefringence data. An increase in conjugation observed for the series of the acids,viz., benzoic,meta-, ortho-, andpara-aminobenzoic acids, results in the increased stability of the complexes with the 11 and 12 composition. In the case ofpara-aminobenzoic acid, the polyhedra [DyL(H₂O)₆]²⁺ and [DyL₂(H₂O)₄]⁺ are cubes with the ligands coordinated to one and two edges, respectively. In the case ofmeta-aminobenzoic acid, the polyhedra [DyL(H₂O)₆]²⁺ and [DyL₂(H₂O)₄]⁺ are a dodecahedron with the ligand coordinated to one edge and a square anti-prism with the ligands coordinated to two edges, respectively. In the case ofortho-aminobenzoic acid, both the 11 and 12 complexes have structures that are intermediate between the structures ofmeta- andpara-aminobenzoic acids.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1767–1770, October, 1994.     

基于自由基配体的Dy(Ⅲ)配合物的设计、合成、结构及磁性

以氮氧自由基为配体,合成了2例未见文献报道的氮氧自由基-稀土配合物[Dy（hfac）₃（NIT-C₃H₅）（H₂O）]与[Dy（hfac）₃（NIT-C₃H₅）]_n（hfac=六氟乙酰丙酮,NIT-C₃H₅=2-环丙烷基-4,4,5,5-四甲基-2-咪唑啉-3-氧化-1-氧基自由基）。单晶结构分析表明配合物1为单核结构,单斜晶系P2₁/c空间群;配合物2为一维结构,单斜晶系P2₁/c空间群。交流磁化率测试结果表明配合物2虚部表现出频率依赖,这表明配合物2是单链磁体。     

Butterfly‐Shaped Pentanuclear Dysprosium Single‐Molecule Magnets

Two new “butterfly‐shaped” pentanuclear dysprosium(III) clusters, [Dy₅(μ₃‐OH)₃(opch)₆(H₂O)₃] ? 3 MeOH ? 9 H₂O ( 1 ) and [Dy₅(μ₃‐OH)₃(Hopch)₂(opch)₄(MeOH)(H₂O)₂] ? (ClO₄)₂ ? 6 MeOH ? 4 H₂O ( 2 ), which were based on the heterodonor‐chelating ligand o‐vanillin pyrazine acylhydrazone (H₂opch), have been successfully synthesized by applying different reaction conditions. Single‐crystal X‐ray diffraction analysis revealed that the butterfly‐shaped cores in both compounds were comparable. However, their magnetic properties were drastically different. Indeed, compound 1 showed dual slow‐relaxation processes with a transition between them that corresponded to energy gaps (Δ) of 8.1 and 37.9 K and pre‐exponential factors (τ₀) of 1.7×10^?5 and 9.7×10^?8 s for the low‐ and high‐temperature domains, respectively, whilst only a single relaxation process was noted for compound 2 (Δ=197 K, τ₀=3.2×10^?9 s). These significant disparities are most likely due to the versatile coordination of the H₂opch ligands with particular keto–enol tautomerism, which alters the strength of the local crystal field and, hence, the nature or direction of the easy axes of anisotropic dysprosium ions.