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1.
铽与邻氨基苯基苯甲酸配合物的合成、表征及荧光性质   总被引:2,自引:0,他引:2  
选择不同的pH值,在乙醇-水溶液中合成了铽与邻氨基苯基苯甲酸固体配合物.通过元素分析、摩尔电导、热分析、红外光谱、紫外光谱,表征并确定了配合物的化学组成为TbL4K·nH2O(n=1,2).同时,在不同pH值下合成得到的配合物的荧光性质也得到了测试和讨论,表明pH=10.0时配合物TbL4K·2H2O在544 nm处5D4→7F5跃迁的发射峰为最强.  相似文献   

2.
王春燕  吴小说  李夏 《应用化学》2008,25(4):455-458
2.羧基肉桂酸、Tb(NO3)3·6H2O2和邻菲哕啉按物质的量1.5:1:1溶于乙醇溶液,用2 mol/L NaAc溶液调节混合溶液的pH值至5左右,用无水乙醚扩散的方法得到了一种新的配合物Tb(Ac),(phen):(Ac-=乙酸根).利用x射线单晶衍射分析确定了标题配合物的晶体结构.该晶体属于单斜晶系,Cc空间群,晶胞参数为a=1.164 5(2) nm.b=1.792 56(3)nm,c=1.30363(3)nm ,α=90.000,β=100.516 0(10)0,γ=90.000,M=696.47.V=2.56514(7)nm,3,Z=4,F(000)=2436,R(int)=0.0297.中心Tb3 离子与3个Ac-的6个羧基O原子和2个Phen分子的4个N原子配位.3个Ac-阴离子以螯合双齿一种配位方式与Tb3 离子配位,形成了3个四元环.2个Phen分子也以螯合双齿配位的方式与Tb3 离子配位,形成了2个五元环.中心Tb3 的配位数为10,Tb3 离子的配位环境可描述为扭曲的双帽四方反棱柱.在配合物的荧光光谱中,在491、543、584和615nm处出现4条谱线.分别对应于Tb3 离子的5D4→7F6、5D4→7F5、5D4→7F3和5D4→7F3跃迁.  相似文献   

3.
用两种方法分别将四足配体铽配合物[TbL(NO3)]^2+和[TbL]^3+插层组装到了蒙脱土(MT)层板间,制备出超分子复合发光材料[TbL(NO3)^2+-MT和[TbL]^3+-MT。方法一:通过离子交换反应让配离子[TbL(NO3)]^2+取代钠+基蒙脱土(Na-MT)中的Na^+离子,插层组装到蒙脱土层板间。方法二:用配体L与铽基蒙脱土(Tb-MT)反应,使配体插入蒙脱土层板间与Tb^3+离子配位。用元素分析、XRD,FT-IR,UV-vis和热分析对材料进行了表征,并对其荧光性质进行了研究。结果表明,复合材料保持了蒙脱土良好的层柱结构特征,其层间距d001值与插层配离予的直径吻合较好,配离子以单层形式分布于蒙脱土层板间,复合材料中配合物的热稳定性有明显提高。在紫外光激发下,复合材料发出较强的Tb^3+特征荧光,其发射光谱与相应配合物的发射光谱很相似;复合材料中配合物的相对荧光强度较相应纯配合物有明显提高。荧光寿命较长;配合物的激发波长向可见光区发生位移,说明插层组装实现了对配合物激发波长的调制作用。  相似文献   

4.
通过草酸钾(k2ox·H2O)、硝酸镉[Cd(NO3)2·4H2O]和1,10-邻菲咯啉(phen)在甲醇·水溶液中的反应合成了一种双核镉配合物[Cd2(phen)2ox(NO3)2(H2O)2],其结构经单晶X射线衍射表征.配合物属三斜晶系,P(1)空间群,晶胞参数:a=0.67629(14)nm,b=1.0051(2)nm,c=1.0527(2)nm,α=109.19(3)°,β=92.12(3)°,γ=93.48(3)°,γ=0.6733(2)nm3,Z=1,D=2.055 g/cm3,F(000)=410,μ=1.660mm-1,R=0.0445,wR=0.0877.配合物为草酸根桥联的双核镉配合物,且草酸根C-C键中点为配合物的倒反中心,镉与ox2-,phen,NO3-和水配位.运用晶体场理论计算了其态密度,结果表明NO3-和phen对配合物的性质有重要影响.  相似文献   

5.
Cd-Ln杂双核配合物的合成、结构及发光性质   总被引:1,自引:0,他引:1  
采用混合溶剂热方法合成了3个新颖的杂双核d-f配合物, [LnCd(C8H7O3)5(phen)(H2O)](Ln=Dy(1), Pr(2), Gd(3); C8H7O3=对甲氧基苯甲酸根, phen=1,10-菲啰啉), 通过单晶X射线衍射确定了配合物的晶体结构. 结果表明, 3个化合物是同构的. 在同一个分子中, Cd2+与Ln3+通过3个对甲氧基苯甲酸根桥联, Cd2+为五配位, Ln3+为八配位. 在晶体中, 两个相邻的分子被氢键连成二聚体. 测定了3个配合物在室温下的IR, UV-Vis-NIR以及激发和发射光谱. 对比分析了化合物的UV-Vis-NIR吸收光谱与发射光谱的关系, 讨论了d-块(d-L部分)对Ln3+发光的影响.  相似文献   

6.
铽、镝-3-噻吩乙酸二元、三元配合物的合成及表征   总被引:1,自引:0,他引:1  
合成了四种新型的铽、镝的二元、三元配合物.通过元素分析、EDTA配位滴定分析表明其通式为RETh3·2H2O,RETh3phen(RE=Dy,Tb;Th=3-噻吩乙酸根;phen=1,10邻菲啰啉);对配合物进行了紫外光谱、红外光谱、荧光光谱、热重分析.结果表明,二元配合物在100℃左右失去结晶水,三元配合物具有较好的稳定性;在TbTh3phen中,3-噻吩乙酸和邻菲啰罗啉能很好地将能量传递给Tb3+离子,Tb3+离子546nm绿色荧光发射峰最强.  相似文献   

7.
赵丽娜  吴伟娜  袁文兵  闫兰 《应用化学》2007,24(9):1098-1100
合成了一种新的芳香族酰胺配体2,2’-(1,2-亚苯基二氧)二(N-苯基乙酰胺)及其稀土(La,Eu,Tb,Dy,Sm,Gd)硝酸盐配合物,通过核磁共振谱、元素分析、摩尔电导、红外光谱、差热等测试技术对其进行了结构表征。结果表明,稀土配合物的可能结构为:[REL(NO3)3]·H2O(RE:La^3+、Sm^3+、Eu^3+、Gd^3+、Tb^3+、Dy^3+).配合物产率约为78%。在稀土配合物中,作为抗衡阴离子的3个硝酸根均以双齿的配位方式与稀土配位,稀土配位数为10,并且还有1个结晶水。在298K下对配合物[EuL(NO3)3]·H2O和[TI)L(N03)3]·H2O的固体荧光性质进行了研究。结果发现,它们分别发射Eu^3+和Tb^3+稀土离子的特征荧光,且配合物[TbL(NO3)3]·H2O的荧光比[EuL(NO3)3]·H2O的荧光强。说明此芳香族酰胺配体敏论Tb^3+发光比敏化Eu^3+发光程度大。  相似文献   

8.
合成了对甲基苯甲酸铕与2,2′-联吡啶的晶体配合物,元素分析表明配合物的化学式为Eu(p-MBA)_3dipy(p-MBA:对甲基苯甲酸根;dipy:2,2′-联吡啶).用X射线衍射法测定了配合物的单晶结构,其结构式为Eu_2(p-MBA)_6(dipy)_2,属单斜晶系,C2/c空间群,晶胞参数:a=1.4086(6),b=1.9115(11),C=2.3077(16)nm;β=96.60(4)°,V=6.1727nm~3,Z=4.对甲基苯甲酸根,2,2′-联吡啶均以双齿配位,中心铕离子的配位数为八,形成的配位多面体为三角十二面体.两个铕离子通过四个对甲基苯甲酸基桥联,形成双核配合物.利用配合物Eu(p-MBA)_3dipy在紫外光或可见光激发下,能发出很强荧光的特性,以Eu(Ⅲ)离子为光谱探针,77K下测得其高分辨激发和发射光谱及时间分辨光谱,光谱数据表明配合物中有两种Eu(Ⅲ)离子格位.  相似文献   

9.
以异烟酸和邻菲咯啉(phen)为原料,采用水热合成方法,合成了一个新的配位聚合物{[Cd2(phen)2(H2O)2(C6H5NO2)2]·(ClO4)}n,测定了其晶体结构。结果表明:该配合物晶体属单斜晶系,空间群P2√n。与中心镉(Ⅱ)离子配位的3个氧原子分别来自2个异烟酸根和1个水分子,3个氮原子分别来自1个异烟酸根和1个邻菲咯啉,形成六配位变形八面体结构。由于异烟酸的桥联作用及氢键作用,配合物堆积成三维网状结构;同时配合物通过异烟酸的羧基双齿桥联配位以及邻菲咯啉和水分子作为端基配位,形成了双核笼状结构,其Cd(Ⅱ)…Cd(Ⅱ)距离为0.8798 nm。此外,还研究了该聚合物的荧光性质。  相似文献   

10.
以柔链配体癸二酸(C10H18O4)为第一配体、邻菲啰啉(phen)为第二配体合成了三个过渡金属配合物[Mn2(C10H16O4)2(phen)4(H2O)].4H2O(1)、[Cu(C10H16O4)(phen)(H2O)].3H2O(2)、[Cd(C10H16-O4)(phen)].3H2O(3).用元素分析、红外光谱、热重分析等手段表征了配合物;用单晶X射线衍射测定了配合物的结构;其中配合物1和2为癸二酸根桥连的双核结构,配合物3为含有双核节点的配位聚合物.在配合物1中发现了水分子的二聚体,在配合物2中则发现了一维水链,并在配合物3中发现了四元环的六聚水,这些片断通过氢键作用稳定地存在于晶格空隙中,这三种配合物均含有多孔的无限隧道.用溴化乙锭荧光探针法测试了三个配合物对EB-DNA复合体系的荧光猝灭效应,实验结果显示三个配合物均能使EB-DNA复合体系的荧光发生不同程度的猝灭,由此推测配合物均与DNA发生了不同程度的插入作用,其中配合物1的插入作用最强.  相似文献   

11.
Species of empirical formula C4H2O have been invoked either as elusive intermediates in flames or oxidations on heterogeneous catalysts, or as long‐lived species in the interstellar medium. Butatrienone has been characterized experimentally, but isomers ethynyl ketene, butadiynol, and trifulvenone have been described only by computational modeling. Triafulvenone is of special interest as the ketene analog of the carbonyl compound cyclopropenone; both species contain seriously strained three‐membered rings. In contrast to cyclopropenone, which is detected in the interstellar medium, triafulvenone continues to elude experimental capture. The contrast is attributed to a degree of aromatic stabilization in cyclopropenone and anti‐aromatic destabilization in triafulvenone. In this report, we characterize the structure, vibrational and electronic spectra, and thermochemistry for triafulvenone and three of its isomers, butatrienone, ethynyl ketene, and butadiynol to assist experimental detection of these elusive species. Our calculations have shown that triafulvenone is the least stable of these four isomers; even the well‐known butatrienone, is not the most stable. The so far undetected ethynyl ketene is thermodynamically the most stable of these isomers. To facilitate experimental detection of these species we provide vibrational frequencies calculated using both B3LYP/cc‐pVTZ and MP2/cc‐pVTZ level model chemistry corrected for anharmonicity including the possibility that the spectra may include overtones and combination bands for these species The regions of intense IR absorption and most important frequencies are also underlined for all the species involved. To guide the search for short‐lived C4H2O species, we also characterize the optical spectrum. © 2015 Wiley Periodicals, Inc.  相似文献   

12.
The Raman (3200 to 10 cm–1) and infrared (3500 to 50 cm–1) spectra of vinyl chloroformate, H2C=CHOC(O)Cl, have been recorded for both the gas and solid. Additionally, the Raman spectrum of the liquid has been recorded, and depolarization ratios have been obtained. These data have been interpreted on the basis that the only stable conformation present at ambient temperature is thetrans-trans rotamer, where the firsttrans refers to the vinyl moiety relative to the O—CCl bond and the second to the C—Cl bond relative to the=C—O bond. Using harmonic rigid asymmetric top calculations, the infrared vapor phase contours for the C=O and the C=C stretch were predicted for thetrans-trans and for thecis-trans conformer, and were compared with experiment. For both fundamentals thetrans-trans hybrid reproduces the experimental contour, whereas thecis-trans contours fail to do so for both fundamentals. From far-infrared spectrum of the vapor obtained at 0.1 cm–1 resolution, the C(O)Cl andO-vinyl torsional fundamentals have been observed at 132 and 61 cm–1, respectively. Ther 0 structural parameters have been obtained from a combination of ab initio calculated parameters with appropriate offset values and the fit of the microwave rotational constants for the two naturally occurring chlorine isotopes. The structure, barrier to internal rotation, and vibrational frequencies have been determined from ab initio Hartree-Fock gradient calculations, using the 3-21G* and 6-31G* basis sets. These results are compared to those obtained experimentally and to similar quantities for some related molecules.  相似文献   

13.
Infrared spectra (4000–50 cm−1) of the vapor, amorphous and crystalline solids and Raman spectra (3600–10 cm−1) of the liquid with qualitative depolarization data as well as the amorphous and crystalline solids of methylaminothiophosphoryl difluoride, CH3N(H)P(=S)F2, and three deuterated species, CD3N(H)P(=S)F2, CH3N(D)P(=S)F2, and CD3N(D)P(=S)F2, have been recorded. The spectra indicate that in the vapor, liquid and amorphous solid a small amount of a second conformer is present, whereas only one conformer remains in the low temperature crystalline phase. The near-infrared spectra of the vapor confirms the existence of two conformers in the gas phase. Asymmetric top contour simulation of the vapor shows that the trans conformer is the predominant vapor phase conformer. From a temperature study of the Raman spectrum of the liquid the enthalpy difference between the trans and near-cis conformers was determined to be 368±15 cm−1 (4.41±0.2 kJ/mol), with the trans conformer being thermodynamically preferred. Ab Initio calculations with structure optimization using the 6-31G(d) and 6-311+G(d,p) basis sets at the restricted Hartree–Fock (RHF) and/or with full electron correlation by the perturbation method to second order (MP2) support the occurrence of near-trans (5° from trans) and near-cis (20° from cis) conformers. From the RHF/6-31G(d) calculation the near-trans conformer is predicted to be the more stable form by 451 cm−1 (5.35 kJ/mol) and from the MP2/6-311+G(d,p) calculation by 387 cm−1 (4.63 kJ/mol). All of the normal modes of the near-trans rotamer have been assigned based on infrared band contours, depolarization values and group frequencies and the assignment is supported by the normal coordinate calculation utilizing harmonic force constants from the MP2/6-31G(d) ab initio calculations.  相似文献   

14.
Syntheses, absorption and fluorescence properties for a series of new enzyme substrates are described, which are derived from 7-hydroxycoumarins possessing electron-withdrawing substituents in position 3. The new substrates are advantageous over existing ones in that they exhibit longwave absorption and fluorescence maxima as well as largeStokes' shifts. In addition, theirpK a values, which are usually between 6.0 and 7.0, allow the direct and continuous kinetic assay of hydrolases such as esterases, phosphatases, and sulfatases.
Synthesen und spektrale Eigenschaften langwellig absorbierender und fluoreszierender Substrate für die direkte und kontinuierliche kinetische Bestimmung von Carboxylesterasen, Phosphatasen und Sulfatasen
Zusammenfassung Die Synthesen und Absorptions- sowie Fluoreszenzspektren einer Reihe neuer Enzymsubstrate werden beschrieben, welche von 7-Hydroxycumarinen mit elektronenziehenden Substituenten in 3-Stellung abgeleitet sind. Die neuen Substrate bieten gegenüber bisherigen den Vorteil langwelliger Absorptions- und Fluoreszenzmaxima sowie großerStokes-Verschiebungen. Die niedrigenpK s -Werte, welche zwischen 6 und 7 liegen, erlauben weiters eine direkte und kontinuierliche kinetische Bestimmung von Hydrolasen vom Typ der Esterasen, Phosphatasen und Sulfatasen.
  相似文献   

15.
The method developed recently for prediction of 1s electron spectra is now extended to the 2p spectra of SiH4, PH3, H2S, HCl, and Ar. The method for X‐ray absorption spectra involves the use of ΔE for the excitation and ionization energies, and application of time‐dependent density functional theory using the exchange‐correlation potential known as statistical average of orbital potentials for the intensities. Additional assumptions and approximations are also made. The best exchange‐correlation functional Exc for the earlier calculation of ΔE in 1s spectra of C to Ne (namely Perdew–Wang 1986 exchange, combined with Perdew–Wang 1991 correlation) is no longer used in this work on 2p spectra of Si to Ar. Instead, recently tested Exc good for 2p core‐electron binding energies (known as OPTX) for exchange and LYP for correlation, plus scalar zeroth‐order regular approximation is adopted here for the ΔE calculations. Our calculated X‐ray absorption spectra are generally in good agreement with experiment. Although the predictions for the higher excitations suffer from basis set difficulties, our procedure should be helpful in the interpretation of absorption spectra of 2p electrons of Si to Ar. In addition, we report calculated results for other kinds of electron spectra for SiH4, PH3, H2S, HCl, and Ar, including valence electron ionizations and excitations as well as X‐ray emission. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2008  相似文献   

16.
Er2O3的光致发光光谱,吸收光谱和Raman光谱   总被引:1,自引:0,他引:1  
在可见激光的激发下,Er2O3粉晶样品的Raman光谱易受Er^3+光致发光光谱的干扰。本文利用同一Raman光谱仪测得Er2O3的高分辨可见光吸收光谱和激发光谱。  相似文献   

17.
The FTIR spectra of four generations of phosphorus-containing dendrimers built of thiophosphoryl, cyclophosphazene and phthalocyanine cores with terminal benzaldehyde and P–Cl groups have been recorded and analyzed. FT-Raman spectra of four generations of phosphorus dendrimers built of cyclotriphosphazene core with terminal benzaldehyde groups have been detected. Their spectral pattern is determined by the ratio Tn/Rn (Tn—number of terminal groups, Rn—number of repeating units). This ratio trends to r − 1 (r—branching functionality of repeating unit), and becomes constant, when the generation number is higher than 3. Experimental IR spectra of dendrimers built of thiophosphoryl, cyclophosphazene and phthalocyanine cores are very closely similar. The dependence of band full width at half height in IR spectra on the number of dendrons is established. The possibility appears to separate the bands assigned to the core, repeating units and terminal groups of dendrimers by difference spectroscopy method.  相似文献   

18.
Preparation of the Halogenonitrilium Salts XCNH+MF6? (X = CI, Br, I; M = As, Sb) and the Trifluoroacetonitrilium Salts CF3CNH+MF6? The halogenonitrilium salts XCNH+MF6? (X = CI, Br, I; M = As, Sb) are synthesized by protonation of cyanogen halides in the superacide system HF/MF5 at low temperature. The synthesis of trifluoroacetonitrilium salts CF3CNH+MF6? (M = As, Sb) is proceeded analogous with trifluoroacetonitrile. All salts are characterized by vibrational and NMR spectroscopy.  相似文献   

19.
Preparation and Spectroscopic Characterization of the Fluorophosphonium Salts X2FPSCH3+MF6? (X = Br, Cl; M = As, Sb) and XF2PSCH3+SbF6? (X = Br, Cl, F) The preparation of the fluorophosphonium salts X2FPSCH3+MF6? (X = Br, Cl; M = As, Sb) and XF2PSCH3+SbF6? (X = Br, Cl, F) by methylation of the corresponding thiophosphorylhalides in the system CH3F/SO2/MF5 (M = As, Sb) is reported. The new salts are characterized by their vibrational and NMR spectra.  相似文献   

20.
Abstract

The recent paper describes the synthesis and characterization of metal (II) 2, 9, 16, 23-tetra-hydroxyphenylimino phthalocyanines (M–OHPhImPc) of Co (II), Cu (II), Ni (II), and Zn (II). The dark bluish green colored tetramino substituted phthalocyanine derivatives are characterized by the various physico-chemical techniques such as elemental analysis, magnetic susceptibility, UV-Visible, IR, powder X-ray diffraction, and thermogravimetric analysis to check the structural integrity, purity, and thermal stability. The variations of magnetic moment as a function of field strength indicated the presence of intermolecular co-operative interactions. The above said compounds were screened for their antibacterial and antifungal activities.  相似文献   

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