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1.
用柠檬酸络合法合成了LaMnO3、LaCoO3和LaFeO3.NO分子红外光谱表明在上述化合物中存在不同类型的不饱和配位阳离子.对于LaFeO3来说,不饱和配位Fe2 的出现与表面缺陷有关;对于LaCoO3和LaMnO3表面来说,主要是不饱和配位Me3 与氧的配位性更强.  相似文献   

2.
L-苏糖酸及其金属化合物的红外光谱研究   总被引:5,自引:0,他引:5  
制备了高纯度的L-苏糖酸及其与钙、镁、锰、钴、镍和锌的化合物,用化学分析和元素分析确定了它们的组成;通过红外光谱分析研究,确定金属离子与L-苏糖酸的羰基氧配位,同时与羧基脱质子配位,而醇羟基质子不解离,金属离子为sp~3杂化,配位数为4。  相似文献   

3.
用羧甲基壳聚糖分别与硝酸铕和硝酸铽反应,制备了羧甲基壳聚糖-铕和羧甲基壳聚糖-铽稀土配合物。用红外光谱和X射线光电子能谱(XPS)等分析测试手段对配合物进行表征。对配合物配位机理进行了初步的研究,配合物中羧甲基壳聚糖中不仅羧基参与了配位,氨基上的N原子和羟基氧原子也参与了配位。  相似文献   

4.
用壳聚糖(CTS)分别与硝酸亚铈,硝酸锆,硫酸镉和硝酸铅在酸性介质中反应,制备了壳聚糖-Ce(Ⅲ)、壳聚糖-Zr(Ⅳ)、壳聚糖-CA(Ⅱ)、壳聚糖-Pb(Ⅱ)四种壳聚糖-重金属离子配合物(用通式M-CTS表示).用红外光谱(IR)、X-ray衍射(XRD)和X射线光电子能谱(XPS)等光谱分析手段对M-CTS进行了结构表征.结果表明:在壳聚糖-Cd(Ⅱ)配合物中的配位原子是壳聚糖-NH2上的N原子,而在壳聚糖-Ce(Ⅲ)、壳聚糖-Zr(Ⅳ)、壳聚糖-Pb(Ⅱ)配合物中不仅壳聚糖-NH2上的N原子参与了配位,同时OH上的O原子也参与了配位.说明不同的重金属离子与壳聚糖之间形成配位键的配位原子是不完全相同的.  相似文献   

5.
Tb3+离子的荧光光谱与其晶体场点对称性的对应关系   总被引:1,自引:0,他引:1  
曾海燕  黄世华 《发光学报》1994,15(4):280-284
本文用量子力学和群论方法,讨论了镧系离子f8电子构型的荧光光谱与其所处的晶体场对称性的对应关系,并以苯甲酸单晶的低温精细光谱为例讨论其近邻配位结构,为用荧光光谱研究f8电子构型的镧系离子近邻配位结构提供参考.  相似文献   

6.
用XPS技术表征了吲哚-3-羧酸与钕离子的配合物,结果表明吲哚酸分子通过羧基的两个氧以双齿配位的形式与钕离子形成配合物;加入含氮的中性配体邻菲咯啉后,它们的配位形式明显改变,配位的3个吲哚酸分子中有部分(1或2)仍以双齿形式配位,其余分子以单齿形式配位,吲哚环中的氮未能与配位,邻菲洛啉中的两个氮原子参与配位,与钕离子形成五元环。  相似文献   

7.
林宜超  邹斌 《波谱学杂志》1984,1(5):451-458
本文测定了用溴乙烷部分季胺盐化聚4-乙烯基吡啶(EBQP4VP)-CU(Ⅱ)络合物的可见光谱和电子自旋共振(ESR)波谱,研究了温度、配位体/Cu(Ⅱ)摩尔比、溶液的pH值和高分子配位体的季胺盐化度(Q)的变化对高分子-Cu(Ⅱ)络合物配位结构的影响。在配位体/Cu(Ⅱ)摩尔比20:1下,随着溶液pH值增大,或是Q值减小,溶液的比浓粘度下降,因而高分子链形态趋于卷曲,催化氢醌的氧化活性增大,此时高分子-CU(Ⅱ)络合物[CuL4](L为高分子配位体)的配位结构呈四方畸变的八面体结构。  相似文献   

8.
报道了稀土离子与三脚架配体N,N-二(2-苯并咪唑亚甲基)-N-(2-吡啶亚甲基)胺(L)和安替吡啉(L′)形成的二元稀土及三元稀土固体配合物的制备. 配合物在不同溶液中的1H NMR,并结合配合物晶体结构、IR及电荷布居计算,探讨了配体在溶液中的配位形式.在CH\-3CN中,配体L以四齿配位,L′用羰基氧 配位,稀土离子在二元与三元配合物中的配位数分别为10和7.在三元配合物中,由于三个L′的空间位阻作用,将阴离子与溶剂分子排斥出稀土离子的配位层.在DMSO中,由于强极性的溶剂分子参与Ln3+的配位竞争,配合物发生了解离.  相似文献   

9.
研究了5(4-缬氨酸丁氧苯基)-10,15,20-三(4-氯苯基)卟啉锌与嘧啶在氯仿溶液中轴配反应光谱和热力学性质。用紫外-可见分光光度法测定了轴向配位反应体系的配位数和平衡常数。用温度系数法求得了轴配反应的标准摩尔焓变和标准摩尔熵变。探讨了温度对轴向配位反应的影响。  相似文献   

10.
李宗群  张敏  裘灵光 《发光学报》2010,31(3):421-426
以对苯二甲酸(H2BDC)为配体,以锌为中心离子,采用沉淀法合成了具有一维结构的金属配合物 纳米晶,将化合物分散到不同浓度的8-羟基喹啉(8-Hq)溶液中,得到系列配位聚合物 。分别用FT-IR和XRD对目标产物的结构进行了表征。固态发光性质研究显示: 及其配位聚合物具有强的发光,配位聚合物随着8-Hq量的增加,其发光发射光谱有规律地红移,表明该配位聚合物能够通过改变8-Hq与骨架材料间的量的比实现对材料发光性质的调控。  相似文献   

11.
运用傅里叶变换红外光谱技术,对DL-2-氨基-4-磺酸基丁酸(DLH)与Na+,Cu2+,Zn2+和Ni2+ 形成的配合物进行了研究,并用元素分析的方法确定配合物的组成。红外光谱显示DLH分子中的—COOH,—NH+3和—SO-3 基团均可与金属离子发生直接或间接的相互作用。不同过渡金属离子与氨基、羧基相互作用的强度顺序均为: Cu2+>Zn2+>Ni2+,其中羧基与不同离子可能采取了不同的配位方式。  相似文献   

12.
Copper complexes with a cyclic D-His-β-Ala-L-His-L-Lys and all-L-His-β-Ala-His-Lys peptides were generated by electrospray which were doubly charged ions that had different formal oxidation states of Cu(I), Cu(II) and Cu(III) and different protonation states of the peptide ligands. Electron capture dissociation showed no substantial differences between the D-His and L-His complexes. All complexes underwent peptide cross-ring cleavages upon electron capture. The modes of ring cleavage depended on the formal oxidation state of the Cu ion and peptide protonation. Density functional theory (DFT) calculations, using the B3LYP with an effective core potential at Cu and M06-2X functionals, identified several precursor ion structures in which the Cu ion was threecoordinated to pentacoordinated by the His and Lys side-chain groups and the peptide amide or enolimine groups. The electronic structure of the formally Cu(III) complexes pointed to an effective Cu(I) oxidation state with the other charge residing in the peptide ligand. The relative energies of isomeric complexes of the [Cu(c-HAHK + H)](2+) and [Cu(c-HAHK - H)](2+) type with closed electronic shells followed similar orders when treated by the B3LYP and M06-2X functionals. Large differences between relative energies calculated by these methods were obtained for open-shell complexes of the [Cu(c-HAHK)](2+) type. Charge reduction resulted in lowering the coordination numbers for some Cu complexes that depended on the singlet or triplet spin state being formed. For [Cu(c-HAHK - H)](2+) complexes, solution H/D exchange involved only the N-H protons, resulting in the exchange of up to seven protons, as established by ultra-high mass resolution measurements. Contrasting the experiments, DFT calculations found the lowest energy structures for the gas-phase ions that were deprotonated at the peptide C(α) positions.  相似文献   

13.
In this paper, various moieties of ethyl, carbazole and oxadiazole are attached to 2-thiazol-4-yl-1H-benzoimidazole to form a series of diamine ligands. Their corresponding Cu(I) complexes are also synthesized using bis(2-(diphenylphosphanyl)phenyl) ether as the auxiliary ligand. Crystal structures, thermal property, electronic nature and luminescence property of these Cu(I) complexes are discussed in detail. These Cu(I) complexes are found to be efficient green-emitting ones in solutions and the emissive parameters are improved largely by the incorporation of substituent moieties. Detailed analysis suggests that the effective suppression of solvent-induced exciplex quenching is responsible for this phenomenon. On the other hand, the introduction of substituent moieties exerts no obvious influence on molecular structure, thermal stability and emitting-energy of the Cu(I) complexes, owing to their absence from inner coordination sphere.  相似文献   

14.
合成了4种新的糖胺 金属配合物,分别为[Ni(HL) (H2 O) 2 ]2 Cl2 ·CH3OH·2H2 O ,[Cu(HL) ]2 Cl2 ·CH3CH2 OH·3H2 O ,[Zn(HL) ]2 Cl2 ·H2 O ,[Co(HL) (H2 O) (OH) ]2 Cl2 ·CH3OH·2H2 O (HLN ,N′ 二βD 葡萄糖基乙二胺) ,并用元素分析、红外、紫外、核磁共振氢谱对其结构进行了表征。结果表明,Ni(Ⅱ) ,Co(Ⅲ)配合物为八面体构型,而Cu(Ⅱ) ,Zn(Ⅱ)配合物为四面体构型。最后研究了其对对硝基苯吡啶甲酸酯(PNPP)催化水解的催化速率常数。  相似文献   

15.
X‐ray absorption fine structure spectra have been investigated at the K‐edge of copper in copper(II) salen/salophen complexes: [Cu(salen)] (1), [Cu(salen)CuCl2].H2O (2), [Cu(salophen)] (3) and [Cu(salophen) CuCl2].H2O (4), where salen2? = N,N′‐ethylenebis (salicylidenaminato); salophen2? = o‐phenylenediaminebis(salicylidenaminato). Complexes 1 and 3 are supposed to have one type of copper centers (called (Cu1)) and complexes 2 and 4 two types of copper centers (called (Cu1) and (Cu2)) having different coordination environments and geometries. A theoretical model has been generated using the available crystallographic data of complex 1 and it has been used for analysis of the extended X‐ray absorption fine structure (EXAFS) data of the four complexes to obtain the structural parameters for (Cu1) center. For this center, the obtained Cu–Cu distance (3.2 Å) verifies the binuclear nature of all the complexes. For determining the coordination geometry around (Cu2) center in 2 and 4, a theoretical model has been generated using the crystal structure of a Cu(II) complex, [Cu(C16H12N2O2Cl2)]. This theoretical model has been fitted to the EXAFS data of 2 and 4 to obtain the structural parameters for (Cu2) center. The present analysis shows that (Cu1) center has square pyramidal geometry involving 2N and 3O donor atoms, whereas (Cu2) center has distorted tetrahedral geometry with 2O and 2Cl donor atoms. The values of the chemical shifts and presence of typical Cu(II) X‐ray absorption near‐edge spectroscopy features suggest that copper is in the +2 oxidation state in all these complexes. The intensity of ls → 3d pre‐edge feature has been used to investigate the geometry and binuclear nature of the complexes. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

16.
合成了两种新的铜(Ⅱ)-天冬氨酸-咪唑类混配配合物([Cu(HAsp)ImH2O]SO4·4H2O与[Cu(Asp)Im (OH)]·4H2O,HAsp代表天冬氨酸分子,Asp代表天冬氨酸离子,Im代表咪唑)。以元素分析、红外光谱及热重-差热分析对其进行表征;以电子吸收光谱法及荧光分析法研究了这两种配合物与DNA的作用。结果表明:两种铜(Ⅱ)-天冬氨酸-咪唑类混配配合物与DNA的作用方式明显不同:[Cu(HAsp)ImH2O]SO4·4H2O为伴随着静电作用的插入结合;而[Cu(Asp)Im (OH)]·4H2O主要与DNA的碱基N发生配位作用,造成了DNA双螺旋的破坏。分析了两种配合物因结构不同而导致的与DNA作用方式不同的原因。  相似文献   

17.
Studies on speciation have been done in the mixtures of mixed ligand copper complexes. Three heterogeneous mixtures have been studied, each having one Cu(I) complex and one Cu(II) complex. The Cu(I) complex is [Cu(thu)Cl 0.5H2O] (1) and the Cu(II) complexes are [Cu(L-phen)(bpy) H2O] (2), [Cu(L-tyr)(phn) 2.5H2O] (3), and [Cu(dien)(ina) 4H2O.1/2SO4] (4) (where thu = thiourea, phen = 1,10-phenanthroline, bpy = 2,2′-bipyridine, tyr = tyrosine, dien = diethylenetriamine, and ina = isonicotinate anion). The mixtures have been prepared by mixing the Cu(I) complex with each of the Cu(II) complexes in the ratio of 1:1 by mole percentage. The X-ray absorption fine structure (XAFS) spectra have been recorded at the K-edge of copper in the mixtures as well as in the complexes, separately. The aim of the present work is to make a study of the different methods of speciation using XAFS, viz., principal component analysis (PCA) and the target transformation (TT) method, the linear combination fitting (LCF) method, derivative spectra methods, and normalized difference absorption edge spectra (NDAES) analysis. It has been shown that these methods can be used to determine the relative quantity of the mixed ligand complexes in their mixtures.  相似文献   

18.
苯并咪唑取代胺及其配合物光谱分析   总被引:9,自引:1,他引:8  
本文阐述了用原子吸收光谱测定三(2-苯并咪唑亚甲基)胺和二(2-苯并咪唑亚甲基)胺与Cu2 的配合物中心原子,并对上述配体及配合物用紫外光谱法和红外光谱法进行了研究,从而解释了配合物分子结构。  相似文献   

19.
Two 1,8-naphthyridines were synthesized and found to be fluorescent in solution. These compounds were studied in the presence of Cu(+) and Cu(2+) ions and it was verified that the metal causes the quenching of their fluorescence emission, due to the formation of complexes between the naphthyridine and the metal. A displacement assay was carried out in a DMSO-water mixture with the addition of various anions to the solutions of the complexes, and it was observed that these systems have a high capacity to selectively detect cyanide.  相似文献   

20.
8—羟基喹啉金属螯合物的吸收光谱和发射光谱   总被引:3,自引:0,他引:3  
测量了一系列8-羟基喹啉金属螯合物的吸收谱和发射谱,发现当喹啉螯合不同的金属阳离子,其各类光谱有不同程度的红移,本文经验地给出了8-羟基喹啉金属螯合物发射谱和吸收谱移动的规律并分析了金属离子影响光谱原因。  相似文献   

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