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181.
在水热条件下合成了一个二维稀土铽的配位聚合物[Tb(cam)(H2O)3]n·nH2O) (1)(H3cam=4-羟基吡啶-2,6-二羧酸),通过元素分析、红外光谱、X-射线单晶衍射、荧光、紫外吸收、热重分析和X-射线粉末衍射对其进行表征。Tb(Ⅲ)离子八配位呈十二面体几何构型。每个Tb(Ⅲ)离子与3个(cam)3-离子相连形成具有(4·82)型拓扑的二维层状结构,层与层之间通过氢键的识别作用拓展为三维超分子结构。室温下配合物1呈现出稀土Tb3+的特征荧光发射峰,且发光强度较大,说明配体的能级与TbⅢ离子的发射能级比较匹配。 相似文献
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183.
A novel terbium coordination polymer {[Tb(TCB)1/2(H2TCB)1/2(H2O)](H2O)2}n (H2TCB = 1, 2, 4, 5‐benzenetetracarboxylic acid) ( 1 ) has been hydrothermally synthesized and determined by single crystal X‐ray diffraction method, which features a very interesting three‐dimensional framework with large packing cavities. It crystallizes in the monoclinic space group P21/n with a = 1.0723(4) nm, b = 0.7168(3) nm, c = 1.7155(6) nm, β = 97.079(4)°, V = 1.3086(8) nm3, Z = 4, and final R1 = 0.0203, wR2 = 0.0404. In 1, the protonated carboxylate groups are free, the other carboxylate groups are bonded to Tb3+ ion in three modes: the chelating bidentate, the bridging bidentate and bridging tridentate. Moreover each Tb3+ ion is coordinated by nine oxygen atoms from six carboxylate groups and one water molecule respectively to complete a deformed tricapped trigonal prismatic geometry. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
184.
185.
酰胺型三足配体硝酸铽超分子配合物的晶体结构与荧光性质 总被引:4,自引:1,他引:3
通过硝酸铽与新型酰胺型三足配体L (2,2',2'-胺三乙酰苯胺)之间的反应得到配合物[TbL2(H2O)]• (NO3)3(H2O)2(CH3OH), 并用X射线单晶衍射测定了配合物的晶体结构. 配合物为酰胺型三足配体稀土硝酸盐配合物中首例1∶2 (M∶L)型配合物. 配合物为单斜晶系, P21/c空间群, 晶胞参数a=1.2870(7) nm, b=1.6590(8) nm, c=2.8723(12) nm, β=115.364(2)°, V=5.5415(5) nm3, Z=4, R=0.0399, wR=0.0922, Tb3+为9 配位, 呈变形的三帽三角棱柱配位构型. 配合物分子单元通过分子间氢键作用将整个分子连接成三维网状超分子结构. 室温下, 在紫外光激发下配合物固体表现出Tb3+的特征荧光发射. 相似文献
186.
用燃烧法制备了不同Tb3+掺杂量的Y2O2S:Tb3+纳米发光材料,同时用高温固相法制备了不同Tb3+掺杂量的Y2O2S:Tb3+体相材料,X射线晶体衍射结果表明,制备的纳米材料和体相材料均为单一的Y2O2S相.由Debye-Scherre公式估算得到纳米颗粒的平均粒径大约为10 nm.讨论了纳米材料和体相材料Y2O2S:Tb3+中Tb3+的掺杂浓度对荧光性能的影响.激发光谱表明纳米材料的基质吸收带与体相材料相比向高能端移动了6nm,应用久保理论对此进行了定性的解释. 相似文献
187.
合成了一系列Eu3+和Tb3+与 2 ,3-吡啶二甲酸 (简称H2 QUI)的单核、同多核及它们分别与非荧光性稀土离子La3+,Gd3+,Y3+的异多核配合物 ,并对单核配合物分别引入含氮配体 1,10-邻菲咯啉 (简称 phen)和 2 ,2’ -联吡啶 (简称 2 ,2’ -bipy)生成三元配合物。对这些配合物进行了红外 相似文献
188.
The supramolecular terbium complex, {[Tb(SIP)(H2O)5]2(bpy)3(H2O)}n (NaH2SIP = 5-sulfoisophthalic acid monosodium salt and bpy = 4,4'-bipyridyl), has been synthesized by the hydrothermal reaction of Tb4O7 with NaH2SIP and bpy at 165 ℃, and characterized by single-crystal X-ray diffraction, elemental analysis, IR spectrum, powder X-ray diffraction and photoluminescence spectrum. It crystallizes in a monoclinic system, space group C2/c, with a = 30.6840(1), b = 10.9206(2), c = 17.4967(3) A, β= 111.931(1)°, V = 5438.65(14) A^3, Z = 4, C46H52N6O25S2Tb2, Mr = 1470.90, Dc = 1.796 g/cm^3, p = 2.747 mm^-1, F(000) = 2928, the final R = 0.0654 and wR = 0.1322 for 3806 observed reflections with I 〉 2σ(I). In the neutral [Tb(SIP)(H2O)5]2 motif, the Tb(III) ions are linked by the SIP ligands to form a one-dimensional zigzag chain propagating along the c axis. The zigzag chains are linked together by hydrogen bonds and π-π stacking interactions to form a two-dimensional supramolecular framework. The uncoordinated bpy molecules act as pillars to extend the two-dimensional sheets into a distinctive pillared three-dimensional supramolecular structure through O-H...N hydrogen bonds. The photoluminescence of the complex was investigated at room temperature in the solid state. 相似文献
189.
《Analytical letters》2012,45(14):2293-2308
Abstract A new spectrofluorometric method was developed for determination of coenzyme II. We studied the interactions between balofloxacin–terbium(III) complex and coenzyme II by using ultraviolet–visible absorption and fluorescence spectra. While balofloxacin–terbium(III) was used as a fluorescence probe, under the optimum conditions, coenzyme II could remarkably enhance the fluorescence intensity of the balofloxacin–terbium(III) complex at λ = 545 nm, and the enhanced fluorescence intensity was in proportion to the concentration of coenzyme II. Optimum conditions for the determination of coenzyme II were also investigated. The dynamic range for the determination of coenzyme II was 6.0 × 10?8 to 6.0 × 10?6 mol L?1, and the detection limit (3σ/k) was 3.5 × 10?8 mol L?1. This method was simple, practical, and relatively free interference from coexisting substances and could be successfully applied to determination of coenzyme II in synthetic samples. The mechanism of fluorescence enhancement of balofloxacin–terbium(III) complex by coenzyme II was also discussed. 相似文献
190.
《Journal of Coordination Chemistry》2012,65(3):499-504
Abstract Complexes with composition Ln2(β-diketonate)6 (dmm) (Ln = Eu, Tb; dmm = 2,6-dimethyl-morpholine; β-diketonate = 4,4,4-trifluoro-l-(2-thienyl)-l,3-butanodionate (tta); 4,4,4-tri-fluoro-1-phenyl-1,3-butanodionate (tfpb) and l,l,l-trifluoro-l,4-pentanedionate (tfa)) have been synthesized. The adducts were characterized by microanalyses, IR spectra and emission spectra at room temperature and at 77K. The spectra of europium complexes indicate the oligomeric at least dimeric, nature of the compounds, since the bands are broad. The number of peaks in all cases was interpreted as C3V symmetry around the central ion. 相似文献