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1.
Introduction The chemistry of the sandwich-type heteropoly-oxometalates encapsulating clusters of early transition metals is current of considerable interest with respect to the application of complexes in material science, medi-cine, catalysis and fundamental perspectives.1-4 The great advantage of these complexes is the possibility of varying either the type of the metallic cluster or the het-eroatom. The proximity of the transition metals pos-sessing unpaired electrons facilitates their cou… 相似文献
2.
Ng Seik Weng 《结构化学》2003,22(4)
In their report of the crystal structure of the compound claimed to be [Cu(OH)2(H2O)2(4- C5H4NCOOH)2], the authors did not give any experimental details on the location and refinement of the water and hydroxyl hydrogen atoms[1]; they had assumed the presence of the carboxylic -CO2H unit on the basis of the infrared stretching frequency at 1700 cm-1 that is only of medium intensity. The cell constants for the compound are, in fact, identical, with those documented for tetraaquabis(isonicot… 相似文献
3.
GUO Wen-Juna ZHANG Han-Huia b HUANG Chang-Canga SUN Rui-Qinga CHEN Yi-Pinga CAO Yan-Ninga a 《结构化学》2005,(7)
1 INTRODUCTION It is well-known that bismuth and lead display attractive properties as promoting elements in noble metal-based catalysts[1], and thermal decomposition of ammonium metal oxalates can yield crystalline porous materials with a high surface area. This feature makes them attractive as precursors for catalysts and other nanocrystalline oxides[2]. Because of their topology, the oxalates themselves also possess inte- resting properties such as the capability of ion-exchange. The … 相似文献
4.
Synthesis and Structural Characterization of [(C_2H_5)_4N][V~((V))O_2(OC_6H_3(OCH_3)CHNNCSNH_2)]·H_2O 总被引：1，自引：1，他引：0
1 INTRODUCTIONAlthough vanadium plays an increasingly recognized role as a biometal[1~4], little is known about the structure and function of vanadium compounds in living organisms. A classical and nevertheless rapidly developing field of application for oxovanadates and related compounds is their use as catalysts in polymerization and oxidation reactions[5,6], and recent interest has focused on oxovanadates as model compounds for the interaction of oxovanadates with the active sites of en… 相似文献
5.
1INTRODUCTION Contemporary interest in polyoxovanadates re-flects not only their attractive magnetic and electro-nic properties[1~3],but also the complex structural chemistry of vanadium with a variety of coordina-tion geometries and oxidation states[4].Decavana-date is a represent of the fully oxidized isopolyva-nadates.A number of compounds have been repo-rted and characterized[5~9],but it is found now that most of these polyvanadate salts coordinated with metal cations are actually eith… 相似文献
6.
1 INTRODUCTION The investigation of Shiff base complexes con- taining sulfur and complexes of amino acid Schiff bases[1, 2] has recently aroused considerable interest due to their antiviral, anticancer and antibacterial activities. Taurine, known as 2-aminosulfonic acid, is indispensable to human beings and plays an im- portant role in physiological functions. In this con- tribution, we present the synthesis and crystal struc- ture of a new binuclear Zn(II) dimmer with a tri- dentate Sc… 相似文献
7.
1 INTRODUCTION Organic-inorganic hybrid materials and polyoxo-metalates have received much attention because of their intriguing structural diversity and potential applications in molecular adsorption, ion exchange, heterogeneous catalysis and nanotech nology as well as in electrical, magnetic and photochemical areas[1, 2]. One of the important ad- vances in the design of new organic-inorganic hybrid materials is utilizing poly- oxometalates’ coordination ability to produce poly- oxoanio… 相似文献
8.
1 INTRODUCTION There is considerable interest in the heteropolymetalates in view of their potential applications in many fields, such as, catalysis, biology, medicine, magnetochemistry, and materials science[1～5]. It has been well- known that the rare earth elements are highly oxophilic and the anion of polyoxomolybdates have oxygen-rich composition, which can be used as synthons for the construction of novel heteropolymetalates. Since the structure of polyoxoanion 36-molybdate Mo36O1128… 相似文献
9.
One-dimensional chain copper(Ⅱ) coordination polymer has been synthesized and characterized in the solvent mixture of water and alcohol with o-acetamidobenzoic acid,4,4'-bipyridine and copper perchlorate.It is of tetragonal,space group P41212 with a=1.57756(10),b= 1.57756(10),c=2.1438(3)nm,V=5.3352(8) nm3,Dc=1.524 g/cm3,Z=4,F(000)=2536,R= 0.0479 and wR=0.0979.The crystal structure shows two coordination modes.The copper(1) is coordinated with two nitrogen atoms of one 4,4'-bipyridine molecule and two oxygen atoms from two o-acetamidobenzoic acid molecules,forming a distorted tetrahedral coordination geometry;the copper(2) is coordinated with two nitrogen atoms of one 4,4'-bipyridine molecule,four oxygen atoms from two o-acetamidobenzoic acid molecules and two water molecules,generating a distorted octahedral coordination geometry.The result of TG analysis shows that the title complex is stable below 180.0 ℃. 相似文献
10.
《结构化学》1984,(2)
<正> Introduction. Tertiary diphosphine-cyclopentadienyl-nickel(Ⅱ) complexes were first synthesized by Sato (Sato, et al., 1971), and their boronhydrides were prepared by Zhang (Zhang, et al., 1983). Here we report the crystal structure of the title compound in Order to correlate the reactivity of this type of compounds with their structures and bondings. 相似文献
11.
1INTRODUCTION Recently,the design and preparation of coordina-tion polymers with new porous frameworks are of great interest due to their potential functionalities such as catalysis,gas absorption,separation and molecu-lar recognition.In designing1-D,2-D and3-D porous coordination polymers,the selection of appropriate ligands is crucial for determining the structure.The mixed-linker systems of both carboxylates and pyri-dyls have proved to be effective for the preparation of novel coordi… 相似文献
12.
Synthesis and Crystal Structure of 18-Tungstotetranickel(II) diphosphate Na_(10){(PW_9O_(34))_2Ni_4(H_2O)_2}·26H_2O 总被引：1，自引：1，他引：0
CUI Chuan-Peng DAI Jing-Cao DU Wen-Xin WU Li-Ming FU Zhi-Yong HU Sheng-Min WU Xin-Tao② 《结构化学》2001,(4)
1 INTRODUCTIONThe inorganic chemistry concentrating on polyoxometallates, is in a position to connect elementary building blocks and their derivatives in different ways, enabling people to synthesize a large variety of remarkable substances, especially those in the "nanoworld". Of particular importance is the anionic-type which has {MOx}-type building-block units, where M stands for the d block elements in high oxidation states.[1] In 1973 Weakley, Evans and Showell isolated[2] K10P2W1… 相似文献
13.
1 INTRODUCTION Polyoxometalates are metal-oxygen clusters with almost unrivaled versatility, which results from their enormous structural variety, range of sizes, tunable redox properties and fascinating catalytic activi- ties[1~7]. Therein, an important progress in transition metal oxide cluster chemistry has been the study of polyoxoanion-substituted and supported inorganic or organometallic complexes[8, 9]. However, modified polyoxoanions with divalent first-row transition me- tal as c… 相似文献
14.
Introduction Flavonoids exist widely in edible plants, and have pharmacological activity. They played a major role in the successful medical treatments at ancient times, and their uses have been persevered up to now.1-3 Flavonoid sulfates were found in a large number of plant species. They occupy an important position in the field of natu-ral products chemistry since they provide structures consisted of organic and inorganic components. The pharmacological assay revealed that flavonoid sulfat… 相似文献
15.
1INTRODUCTION Recently,cyano-bridged lanthanide-transition me-tal complexes have been extensively investigateddue to their potential applications as precursors in the preparation of rare earth orthoferrites,fluores-cent and magnetic materials[1].Various complexes of this system have been obtained in order to ex-plore the relations between structures and pro-perties by using different ligands,such as DMF,4,4?-bipy,and so on,to fill the coordination sites of lanthanide ions[2～9].But up to… 相似文献
16.
1 INTRODUCTION The complexes of amino acid Schiff base have attracted considerable attention because of their bio- activities[1, 2]. Taurine is a special amino acid in be- ings, and recently the complexes of taurine conden- sation salicylaldehyde Schiff … 相似文献
17.
Jun Wei ZHAO Jing Ping WANG Jing Yang NIU School of Chemistry Chemical Engineering Henan University Kaifeng 《中国化学快报》2005,(12)
Polyoxometalates may be versatile inorganic building blocks for the construction of molecular-based materials. By means of their multiple coordination requirements and oxophilicity, lanthanide cations are suitable to link polyoxometalate building blocks to form new classes of materials with potentially useful magnetic and luminescent properties1-4. Peacock and Weakley studied the interactions between the [α-SiW11 O39]8? isomer and lanthanide cations5, and they reported that the [α-SiW11O39… 相似文献
18.
LI Huan yong GUO Peng jiang HU Rong zu GAO Sheng li ** SHI Qi zhen . Department of Chemistry Northwest University Shaanxi Key Laboratory of Physic Chemistry Xi′an P. R. China . Department of Mathematics Northwest University Xi′an P. R. China 《高等学校化学研究》2003,19(2)
IntroductionRecently,a considerable interest has been fo-cused on the complexes of zinc with amino acidsdue to their excellent additives in medicine foodstuff and cosmetics[1— 6] .The investigation on thethermal behavior and the thermochemistry of somezinc amino acids is important to its further applica-tion,which has been reported in references[4,5 ,7— 1 0 ].However,the studies on solid complexZn( Thr) SO4· H2 O has not been reported,whichcan provide the necessary data and the foundation… 相似文献
19.
FU Ping-ping WANG Xin-long WANG En-bo ** QIN Chao XU Lin . Institute of Polyoxometalate Chemistry Faculty of Chemistry Northeast Normal University Changchun P. R. China . China-Japan Union Hospital Jilin University Changchun P. R. China 《高等学校化学研究》2005,(4)
IntroductionPolyoxometalates(POMs)have been attracting ex-tensive interest in solid state material chemistry due tothe richness of their structures and special properties incatalysis,photochemistry,electro-chromism and mag-netism[1—3].POMs have also attracted increasing inter-est of biochemists because of their potential applicationsas drugs againsttumors and viruses[4—6].Agood way todesign drugs based on POMs is to modify the polyox-oanion frameworks with appropriate chemicals,such asami… 相似文献
20.
1 INTRODUCTION Orotic acid (H3dtpc), an important pyrimidine derivative as the effective precursor in the biosynthesis of pyrimidine base of nucleic acids in living organisms, plays a unique role in bioinorganic and pharmaceutical. Aside from the biological interest, orotic acid is also interesting in coordination chemistry. Its ketonic and enolic tautomers along with asymmetric geometry make it to be a very good versatile polydentate ligand[1~5]. The incorporation of metals into supram… 相似文献