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1.
合成和表征了一系列稀土(钆,铕,铽)的邻(间)苯二甲酸配合物.通过测定了苯二甲酸配体的钆配合物的低温磷光光谱确定其相应苯二甲酸配体的最低三重态能级.同时详细讨论了配合物的发光性能,能级匹配和分子内能量传递机制.  相似文献   

2.
手性双核Salen配合物的合成与谱学性质   总被引:5,自引:0,他引:5  
Six novel chiral dinuclear Salen complexes [Cu2L1·H2O (3a), Cu2L2(3b), Ni2L1·2H2O (4a), Ni2L2(4b), Mn2Cl2L1·H2O (5a), Mn2Cl2L2 (5b)] have been synthesized(L1 and L2 are chiral dimeric Salen ligands with different chain length which were synthesized from (R,R)-diaminocyclohexane, salicylaldehyde, 4,4′-(1,10-decaneoxy)salicylaldehyde, 4,4′-(1,6-hexyloxy)salicylaldehyde). These compounds were charactered by elemental analysis, 1H NMR, FT-IR, UV-Vis and CD spectra. The FT-IR, UV-Vis and CD spectra were discussed and compared with those of monomeric ligand and complex in detail. It was found that the spectra properties of compounds of different chain length were almost alike, and the properties of dimeric and monomeric compound were similar too. Furthermore Cotton effect and Cotton split of CD spectra of these chiral compounds were explained by the exciton interaction theory. It seemed that the direction of Cotton split depend on the configuration of diaminohexane. (R,R)-diaminohexane determine the chirality of Salen compounds as negative, and the positive and negative component of Cotton split lie at higher and lower energy respectively.  相似文献   

3.
半乳糖醇与氯化稀土配合物的合成及荧光光谱研究   总被引:4,自引:1,他引:3  
测定了半乳糖醇铽配合物的晶体结构.结果表明,糖的羟基和水分子同时与稀土离子配位,糖的羟基、水分子及氯离子之间形成广泛的氢键网络.红外光谱结果表明,铕和铽对半乳糖醇具有相同的配位方式.本文还测定了荧光光谱,得到稀土离子的特征光谱.  相似文献   

4.
稀土配合物的发光特性及其能量传递研究   总被引:18,自引:0,他引:18  
利用激光诱导荧光技术研究了稀土铕等金属配合物的发光特性及其能量传递动力学过程.得到了这些稀土配合物中中心离子Eu(3 )的激发光谱,配体的三线态发时光谱和单线态发射光谱;在实验上观察到由于中心离子Eu(3 )的5D2←7F0马跃迁吸收造成的配体发射光谱中的凹陷行为  相似文献   

5.
Lewis acid/base addition between Ln(NO3)3 · 6H2O (Ln = Pr, Nd, Sm, Eu, Tb and Lu) and H2salen [H2salen = N,N′-ethylenebis(salicylideneimine)] gives rise to an array of coordination polymeric structures. Crystal structural analysis reveals that Salen effectively functions as a bridging ligand in these compounds. The size of the lanthanide ions controls the structures of these Salen lanthanide complexes. Two representative structures with one dimensional and two dimensional topologies, viz. [Pr(H2salen)(NO3)3(CH3OH)2]n (1) and [Ln(H2salen)1.5(NO3)3]n [Ln = Pr (2), Nd (3), Sm (4), Eu (5), Tb (6) and Lu (7)] are reported. Luminescent spectra of complexes 4 and 5 exhibit characteristic metal-centered emission lines. However, the characteristic luminescence of the terbium(III) ion is not observed either in solution or in the solid state of complex 6.  相似文献   

6.
Five new 4,5‐dichlorophthalate (dcpa)‐extended lanthanide coordination polymers (CPs) with formulas [Ln2(H2O)(dcpa)3]n (Ln = Tb for 1 , Sm for 2 , Pr for 3 , and Nd for 4 ) and [Yb(H2O)2(dcpa)(Hdcpa)]n ( 5 ) were solvothermally synthesized. Structural determinations demonstrate that CPs 1 – 4 are crystallographically isostructural, exhibiting an infinite two‐dimensional layer with dimeric {Ln2(COO)3} subunits extended by aromatic skeleton of fully deprotonated dcpa2– connectors. In contrast, complex 5 features a one‐dimensional broad ribbon with centrosymmetric {Yb2(COO)2} subunits propagated by pairs of ditopic dcpa2– ligands. Interestingly, the anionic dcpa2– connector can serve as a good antenna ligand to sensitize the characteristic emissions of the different LnIII ions in both the ultraviolet (for 1 – 3 ) and near‐infrared (for 4 and 5 ) regions.  相似文献   

7.
A series of bimetallic lanthanide complexes was prepared from a bimacrocyclic system in which two DO3A units are linked by a m‐xylyl unit appended with either a NO2 or an NH2 group (DO3A=1,4,7,10‐tetraazacyclododecane‐1,4,7‐triacetic acid). The Nd‐, Eu‐, Tb‐ and Yb‐complexes were all luminescent: time‐resolved studies indicated that the lipophilic xylyl group restricts close approach of H2O to the metal centre.  相似文献   

8.
IntroductionTheintramolecularenergytransferprocessandmechanismofrareearthcomplexeswithβ-diketoneshavebeengeneralystudiedandac...  相似文献   

9.
合成了一系列吡唑啉酮类稀土铽、铕、钐、钆、镝的配合物, 并采用元素分析、红外光谱和紫外-可见光谱对其进行了表征, 解析了铕配合物的晶体结构. 测定了配体的三重态能级, 研究了这4种配合物的发光性质. 并通过研究配体到稀土离子的能量传递过程, 合理地解释了这些稀土配合物发光性质的差异.  相似文献   

10.
A series of binary and ternary rare earth complexes with para-substitued benzoic acids and 1,10-phenanthroline were synthesized. The phosphorescence spectra were measured and the lowest triplet state energies of ligands were determined, the phosphorescence lifetimes were obtained and intramolecular energy transfer mechanism between ligands was studied. The luminescence properties were also measured and were in agreement with the prediction. The energy match and intramolecular energy transfer process in these binary and ternary complexes were discussed in detail.  相似文献   

11.
Fu  Xing  GAO  Cheng  Jian  ZHU 《中国化学快报》2003,14(2):138-140
Several new chiral organogallium and indium complexes with chiral Salen(1 and 2) as anxciliary ligands have been synthesized and characterized by elemental analysis,IR,^1H NMR and Mass spectroscopy.For the gallium,Mono and bimetallic complexes were obtained,whereas ring closure complexes of indium were obtained.  相似文献   

12.
Two dinuclear lanthanide complexes with pentadentate ligand 3‐[bis(pyridine‐2‐ylmethyl)amino]propane‐1,2‐diol (H2L), formulated as [Ln2(HL)2(NO3)2(H2O)2] · 1.5NO3 · 0.5I [Ln = Tb ( ZTU‐1 ) and Eu ( ZTU‐2 ); ZTU = Zhaotong University] were synthesized and structurally characterized. ZTU‐1 and ZTU‐2 are isomorphous and feature a butterfly‐like arrangement. The fluorescence properties of ZTU‐1 and ZTU‐2 are investigated and slow magnetic relaxation behavior is observed in ZTU‐1 .  相似文献   

13.
能量转移发光分析   总被引:3,自引:0,他引:3  
本文介绍了能量转移发光分析的理论,技术及其在无机物、有机物和生物活性物质测定等方面的应用。  相似文献   

14.
Sr8MgCe(PO4)7:Eu2+,Mn2+ phosphor with whitlockite‐type structure was prepared by a combustion‐assisted solid‐state reaction. The crystal structure and luminescence properties were investigated. Under UV radiation, Sr8MgCe(PO4)7 host exhibits a violet‐blue emission band from Ce3+ ions. When Eu2+/Mn2+ are doped into the host, the samples excited with 270 nm UV radiation present multicolor emissions due to the energy transfer (ET) from Ce3+ to Eu2+/Mn2+. The emitting color of Sr8MgCe(PO4)7:Eu2+ can be tuned from violet‐blue to yellow‐green, whereas Sr8MgCe(PO4)7:Mn2+ can emit red light. Under excitation with long wavelength at 360 nm, Sr8MgCe(PO4)7:Eu2+ phosphor shows a broadband emission from 390 to 700 nm, which is attributed to the 4f65d1→4f7 transition of Eu2+ without the contribution from Ce3+ emission. Tunable full‐color emitting light can be achieved in the Eu2+ and Mn2+‐codoped Sr8MgCe(PO4)7 phosphor by ETEu–Mn through control of the levels of doped Eu2+ and Mn2+ ions. These results suggest that Sr8MgCe(PO4)7:Eu2+,Mn2+ phosphor has potential applications in NUV chip pumped white LEDs.  相似文献   

15.
阮文娟  刘涛  李瑛  骆树新  朱志昂 《化学学报》2003,61(7):1000-1005
用光谱滴定法研究了手性Salen金属配合物(SalenFe~(III), SalenCo~(II))与 四种咪唑类客体在CH_2Cl_2中的分子识别行为,发现手性Salen金属配合物与咪唑 ,N-甲基咪唑,2-甲基咪唑的配位数为2,与克霉唑的配位数为1。各识别体系缔 合常数的顺序对SalenFe~(III)为: K(Im) > K(2-MeIm) > K(N-MeIm) > K(GMZ), 对SalenCo~(II)为:K(Im) > K(2-MeIm) > K(N-MeIm)。测定的识别反应的△ _rG_m~0, △_rH_m~0, △_rS_m~0表明此类识别反应为放热、熵减少的过程,反应 体系存在焓-熵补偿关系。采用分子力学和量子化学方法进行的理论研究对实验结 果作出了合理的解释。  相似文献   

16.
The synthesis of four lanthanide ion complexes Eu?1, Eu?2, Tb?1 and Tb?2, from the heptadentate tri-arm cyclen (1,4,7,10-tetraazacyclododecane) ligands 1 and 2 that were made in one-pot syntheses is described. These coordinatively unsaturated complexes have two labile metal-bound water molecules, as demonstrated by X-ray crystallography. This was also confirmed by evaluating their hydration state (q~2) by measuring their lifetimes in D2O and H2O, respectively. The above complexes were all designed as being “photophysically silent” prior to the recognition of the anion, since they do not possess antenna that can participate in sensitisation of the Eu(III) or the Tb(III) excited state. However, the two water molecules can be displaced upon anion binding by the appropriate aromatic carboxylates to give ternary complexes in water, through either four- or six-member ring chelates (q~0), or possibly via a monodentate binding. In the case of Tb?1 and Tb?2, large luminescence enhancements were observed upon the formation of such ternary complexes with N,N-dimethylaminobenzoic acid at ambient pH. Such binding and luminescent enhancements were also observed for Tb?1 in the presence of salicylic acid. On all occasions, the anion recognition “switched” the emission “on” over two logarithmic units. At higher concentrations, the emission is reduced possibly due to quenching. In the case of aspirin, the binding was too weak to be measured, indicating that Tb?1 selectively detects salicylic acid, the active form of aspirin in water. In the case of Eu?1 and Eu?2, the affinity of these complexes towards such aromatic carboxylates was too weak for efficient ternary complex formation.  相似文献   

17.
18.
随着稀土在工农业和医疗保健上的广泛应用,稀土的生物无机化学研究受到了普遍的关注.以往的研究多集中在稀土离子的宏观毒理学[1],而研究稀土离子与生物膜的作用较少[2].稀土的生物小分子配体的配合物与生物膜作用的研究则未见报道.本文介绍了用拉曼光谱研究稀土离子及其柠檬酸、二乙三胺五乙酸(DTPA)配合物对二栋相酸乙醇胺(DPPE)脂双层的流动性以及碳氢链的构象转变和晶格有序性排列的影响.1实验部分DPPE系Sigma公司产品。La2O3(99.9%)为跃龙化工厂产品,柠檬酸、DTPA为北京化工厂产品.L3Cl3溶液由L32O3溶于盐酸…  相似文献   

19.
Lanthanide heteropoly compounds K15[Ln(HSiW9O34)2]·28H2O(Ln = La, Ce, Nd), denoted as Ln(SiW9)2, were synthesized and characterized by element analysis, TG-DTA, IR, UV, XPS and XRD. The results show that partial oxygen in Ln(SiW9)2 was coordinated with Ln3- , where Ln-3 was in the inner side of the heteropoly anions, while the fundamental structure of SiW9 had little change. The result was supported by ion exchange experiment.  相似文献   

20.
A series of europium(III) and terbium(III) complexes of three 1,4,7‐triazacyclononane‐based pyridine containing ligands were synthesized. The three ligands differ from each other in the substitution of the pyridine pendant arm, namely they have a carboxylic acid, an ethylamide, or an ethyl ester substituent, i.e., these ligands are 6,6′,6″‐[1,4,7‐triazacyclononane‐1,4,7‐triyltris(methylene)]tris[pyridine‐2‐carboxylic acid] (H3tpatcn), ‐tris[pyridine‐2‐carboxamide] (tpatcnam), and ‐tris[pyridine‐2‐carboxylic acid] triethyl ester (tpatcnes) respectively. The quantum yields of both the europium(III) and terbium(III) emission, upon ligand excitation, were highly dependent upon ligand substitution, with a ca. 50‐fold decrease for the carboxamide derivative in comparison to the picolinic acid (=pyridine‐2‐carboxylic acid) based ligand. Detailed analysis of the radiative rate constants and the energy of the triplet states for the three ligand systems revealed a less efficient energy transfer for the carboxamide‐based systems. The stability of the three ligand systems in H2O was investigated. Although hydrolysis of the ethyl ester occurred in H2O for the [Ln(tpatcnes)](OTf)3 complexes, the tripositive [Ln(tpatcnam)](OTf)3 complexes and the neutral [Ln(tpatcn)] complexes showed high stability in H2O which makes them suitable for application in biological media. The [Tb(tpatcn)] complex formed easily in H2O and was thermodynamically stable at physiological pH (pTb 14.9), whereas the [Ln(tpatcnam)](OTf)3 complexes showed a very high kinetic stability in H2O, and once prepared in organic solvents, remained undissociated in H2O.  相似文献   

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