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1.
Using the tellurium(IV) complex compounds as an example, we study the interrelation between the geometric structure and spectral luminescence properties. We find that, in the series of compounds of Te(IV), which are characterized by the island octahedral coordination of Te(IV) ions, the luminescence intensity depends on the degree of distortion of the Te(IV) coordination polyhedron, the Stokes shift, and the energy of the luminescence transition. We revealed that the considered series of Te(IV) compounds possess reversible thermochromic properties.  相似文献   

2.
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   

3.
Ru络合物及其配体的非线性光学特性   总被引:2,自引:0,他引:2  
罗挺  颜星中 《光学学报》1997,17(11):542-1545
采用四波混频方法测量了Ru络合物在450nm处的三阶极化率和三阶超极化系数,并对不同本体和取代基对三阶超极化系数的影响进行了定量和定性的分析。发现在该类型结构中,取代基的负电性对γ值的影响很大。  相似文献   

4.
In this paper we demonstrate the use of Bayesian analysis methods for the analysis of EXAFS data. We will discuss the physical parameters that may be estimated by the method and demonstrate the applicability of the method to Molybdenum coordination compounds.  相似文献   

5.
In this article, a facile and environmentally friendly method was applied to fabricate BSA-conjugated amorphous zinc sulfide (ZnS) nanoparticles using bovine serum albumin (BSA) as the matrix. Transmission electron microscopy analysis indicated that the stable and well-dispersed nanoparticles with the diameter of 15.9 ± 2.1 nm were successfully prepared. The energy dispersive X-ray, X-ray powder diffraction, Fourier transform infrared spectrograph, high resolution transmission electron microscope, and selected area electron diffraction measurements showed that the obtained nanoparticles had the amorphous structure and the coordination occurred between zinc sulfide surfaces and BSA in the nanoparticles. In addition, the inhibition effects of BSA-conjugated amorphous zinc sulfide nanoparticles on tumor cells growth were described in detail by cell viability analysis, optical and electron microscopy methods. The results showed that BSA-conjugated amorphous zinc sulfide nanoparticles could inhibit the metabolism and proliferation of human hepatocellular carcinoma cells, and the inhibition was dose dependent. The half maximal inhibitory concentration (IC50) was 0.36 mg/mL. Overall, this study suggested that BSA-conjugated amorphous zinc sulfide nanoparticles had the application potential as cytostatic agents and BSA in the nanoparticles could provide the modifiable site for the nanoparticles to improve their bioactivity or to endow them with the target function.  相似文献   

6.
During the last two decades, supramolecular polymers have received great attention and the number of their synthesized compounds is still growing. Although people have long been interested in their crystalline network form it was only until 2005 that the first examples of nano- or microscale coordination polymers particles be demonstrated. This review tries to give an overview of all nano supramolecular compounds which were reported from coinage metal ions, their attributed synthetic procedures and to investigate the relation between the dimensions of coinage metal ions (Cu, Ag and Au) coordination and supramolecular polymers with their nano-structural morphologies and dimensions. Eleven compounds (from twenty compounds) with nano-structure morphology were prepared by sonochemical process and Ag(I) coordination and supramolecular polymer nano-structures can be easily prepared by sonochemical procedures.  相似文献   

7.
尹道乐  章立源 《物理学报》1980,29(6):677-685
用LMTO能带论方法分析了密堆结构复式格子的导带中角动量杂化情况变化的规律。指出异质配位(在最近邻位置上出现电子结构差异大的原子)是显著强化导带的角动量杂化程度的必要条件。结合前人对电子-声子耦合超导原理的研究结果,可以对密堆结构化合物得出如下关系:高Tc高η强的角动量杂化强异质配位。这个原理与A15结构,B1结构及其它多种密堆结构化合物的多方面的实验结果普遍符合。 关键词:  相似文献   

8.
碱金属碱土金属化合物标准熵的拓扑研究   总被引:7,自引:0,他引:7       下载免费PDF全文
定义离子极化力参数 gi.在分子拓扑图的邻接矩阵基础上 ,由 gi 建构极化力连接性指数 mG ,其中 0 G、1G对无机分子有良好的结构选择性 .计算了 6 4种碱金属、碱土金属的氧化物、卤化物、硫化物、硒化物等的 0 G、1G ,发现它们的标准熵与分子的大小及分子中的原子数正相关 ,而与分子中离子的极化力负相关 .这与其标准熵的递变规律相一致 .所以 ,化合物的 0 G、1G必然与其标准熵表现出良好的相关性 .研究结果表明 ,其预测值和实验值基本吻合 ,优于Latimer法以及Randic Kier连接性指数  相似文献   

9.
We report on density-functional-based tight-binding simulations of a series of amorphous arsenic sulfide models. In addition to the charged coordination defects previously proposed to exist in chalcogenide glasses, a novel defect pair, [As(4)](-)-[S(3)](+), consisting of a fourfold coordinated arsenic site in a seesaw configuration and a threefold coordinated sulfur site in a near-planar trigonal configuration, was found in several models. The valence-alternation pairs [S(3)](+)-S-1 are converted into [As(4)](-)-[S(3)](+) pairs under HOMO-to-LUMO electronic excitation. This structural transformation is accompanied by a decrease in the size of the HOMO-LUMO band gap, which suggests that such transformations could contribute to photodarkening in these materials.  相似文献   

10.
We synthesised a series of seven mononuclear and two trinuclear Schiff base coordination compounds. All nine complexes have been analysed by Mössbauer and IR spectroscopy. The Mössbauer spectra reveal a doublet, which are related to the high spin state (S = 5/2) of the iron(III) centres.  相似文献   

11.
We report the results of first-principles calculations carried out within a relativistic density-functional method, on the molecular trimers of the MX2 compounds (with M = Zn or Cd and X = Cl, Br, or I), showing how a distorted tetrahedral coordination of a group-2B metal atom by halogens first arises. The trimers of HgX2 are also discussed, both in unstable and in stable configurations.  相似文献   

12.
At the present more than 80% of the total amount of purchased radioactive compounds are used in clinical practice. The field is dominated by technetium coordination compounds. Increasing knowledge on the coordination, redox-reactions, and radiochemistry of this element was the basis for elaborating first rationales on the chemical reasons for the biolocalization of those compounds.

This has stimulated the exploration of new 99mTc-radiopharmaceuticals. A further acceleration of this fast growing field is expected.  相似文献   

13.
合成了不同摩尔比的苯基羧甲基亚砜高氯酸铽、铥异核配合物 ,对配合物进行了组成分析 ,确定了配合物组成为 (Tb1 -xTmx) L2 (ClO4 ) ·2H2 O(x=0 0 0 0~ 0 2 0 0 ,L=C6 H5SOCH2 COO- )。通过IR光谱及摩尔电导的测定推测了配位情况 ,溶解性实验表明配合物在乙醇、丙酮等极性溶剂中具有很高的溶解性。荧光光谱实验表明 :当 x =0 0 0 1~ 0 10 0时铥对铽的荧光均产生敏化增强效应 ,当x =0 0 0 1时敏化强度最大 ,可使Tb3+ 荧光强度增加 32 6 %。  相似文献   

14.
本文以XL-200型超导NMR谱仪对镧系离子与L-组氨酸配合物进行了一系列的研究,测得微酸性条件下的顺磁诱导位移,对这些诱导位移进行分析计算,得到了各磁性核的配合物生成位移、接触位移和准接触位移,同时以准接触位移为依据,对配合物结构进行模拟,获得了有关的结构参数.并对镧系离子在磁学性质上的特征进行了讨论.  相似文献   

15.
We have used Fourier transform IR spectroscopy methods to study normal mouse lung tissue and also after subcutaneous transplantation of a B-16 melanoma tumor in the tissue. We also studied tissues with B-16 melanoma after they were treated with coordination compounds based on palladium complexes of methylenediphosphonic acid. The IR spectra of the lung tissues with metastases in the region of the C = O stretching vibrations are different from the IR spectra of normal tissue. We identified spectroscopic signs of the presence of metastases in the lung. We show that when a cancerous tumor is treated with a preparation of palladium complexes of methylenediphosphonic acid, the spectroscopic signs of the presence of metastases in the lung are missing. After treatment with the optimal dose of this drug, the IR spectrum of the lung tissue in which multiple metastases were present before treatment corresponds to the spectrum of normal tissue. We have determined the efficacy of the antitumor activity of coordination compounds based on palladium complexes of methylenediphosphonic acid.  相似文献   

16.
壳聚糖中ZnS:Mn纳米微晶的制备及其发光特性   总被引:7,自引:0,他引:7       下载免费PDF全文
金炎  蒋雪茵 《发光学报》1997,18(3):253-257
利用壳聚糖通过离子络合的方法制备了ZnS:Mn纳米微晶。壳聚糖含有一些极性基团,既是分散纳米微晶的有机介质,起到孤立微粒、控制粒度的作用,又具有表面修饰作用。通过改变反应物的浓度,得到微晶的尺寸在4.0~7.0nm(计算值).用激发和发射光谱观察了量子尺寸效应造成的光学性质的变化。用FTIR光谱分析了微晶和壳聚糖间的络合作用。  相似文献   

17.
采用常规溶液反应蒸发法以4-巯基吡啶(简写为4-MPy)为有机配体与银、镉的硝酸盐合成了两种金属有机配合物。并利用红外、拉曼、紫外-可见光谱技术对4-MPy及合成的配位化合物进行了研究,对主要红外和拉曼谱带进行了经验归属,并进一步讨论了配体和配合物的特征吸收谱带与配合物结构间的关系。在红外光谱中,配体在1 459cm-1处的吸收峰归属为CC和CN复合振动峰,形成配合物后在两种配合物中,此吸收峰分别向高波数位移至1 464和1 464cm-1。在拉曼光谱中,两种有机配位化合物在1 004和1 008cm-1处归属为环呼吸振动峰、在1 617和1 615cm-1处归属为环伸缩振动峰、在720和720cm-1处归属为β(C—C)和ν(C—S)的复合振动峰,各自十分相似。  相似文献   

18.
Johannes V. Barth 《Surface science》2009,603(10-12):1533-1541
Surface coordination chemistry has been traditionally associated with analogies between metal–ligand bonding in coordination compounds and chemisorptive interactions, the anchoring of metal complexes or other units for interface functionalisation, or the chemistry of oxide surfaces. However, more recently it became clear that well-defined surfaces similarly represent versatile platforms to conduct metal–ligand reactions in two dimensions and engineer unique coordination compounds or layers by novel complexation or metal-directed assembly protocols. This approach presents a versatile strategy to realize coordinatively unsaturated species as well as metal–organic polymers and networks with distinct shape and functional properties.  相似文献   

19.
镧系配合物的荧光光谱   总被引:8,自引:0,他引:8  
对镧系配合物荧光光谱的研究进展进行了评述,并对其光物理、光化学进行了归纳、分类,特别是对目前研究非常活跃的镧系离子荧光探针法在配合物和生物分子体系结构探测中的应用情况进行了总结。  相似文献   

20.
The aquasonolytical rate constants and products of diethyl sulfide, diallyl sulfide, dipropyl sulfide, dibutyl sulfide, diethyl disulfide, and dipropyl disulfide have been investigated. The sonolysis for model compounds in aqueous solutions follows the pseudo-first-order kinetics. Disulfides are more rapidly sonicated than sulfides. Neither vapour pressure nor thermostability of thioethers can obviously affect their aquasonolytical rates. Higher Henry's Law constant and hydrophobicity of substrate result in a higher aquasonolytical rate constant. Furthermore, the aquasonolytical rate constant decreases as the initial concentration of dipropyl sulfide increases. CS2, COS, thiols, thiirane, lower sulfides, butenyne, and butadiene are detected as principal very volatile products during ultrasonic irradiations. Thiophene, benzene, 1,5-hexadiene, and cyclopentadiene are additionally obtained during the aquasonolysis of diallyl sulfide. Furthermore, trisulfides, trithiolane, and other cyclic thiolanes as volatile products are observed. These results demonstrate that thioethers undergo thermal decomposition during their aquasonolyses. The transfer process of volatile thioethers between cavitation bubbles and bulk liquid remarkably affect the aquasonolysis, and the hydrophobicity of substrate dominates the transfer process.  相似文献   

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