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1.
1 INTRODUCTION The design and synthesis of polynuclear com- plexes have attracted chemists?attention in the contemporary chemistry, since their clusters maybe lead to novel materials with magnetic, optical, electronic and catalytic properties of the constituent metals[1~3]. It is also prevalently interesting to synthesize high-nuclearity metal complexes for their nanoscopic dimensions[3, 4]. Spectroscopic properties of the lanthanides are widely used in the study of biological systems. …  相似文献   

2.
1 INTRODUCTION There has been great and considerable interest in the study of copper nitrite complexes because they are relevant to the study of copper-containing enzymes involved in the denitrification process[1]; in particular, copper-nitrite complexes are potentially relevant to the nitrite reductases[2] (the enzyme from Achromobacter Cycloclastes) which convert NO2- to NO and/or N2O. Many attempts have been made to synthesize a variety of copper-nitrite complexes, in which the n…  相似文献   

3.
毕文华  孙道峰  曹荣  李星  时茜 《中国化学》2004,22(3):271-274
Introduction Recently, many novel polymers with a variety of metal ions have been prepared and structurally characterized owing to the versatility of carboxylate ligands.1-5 Much attention has been devoted to this field partly because polymers of carboxylate ligands are good candidates for the investigation of exchange-coupling interactions between adjacent metal ions. A successful strategy to synthesize these complexes is the reaction of metal salts with properly selected multi-dentate carbox…  相似文献   

4.
1 INTRODUCTION The lanthanide amide complexes are excellent synthetic precursors for lanthanide derivatives, par- ticularly in the reactions involving protonic rea- gents[1]. A few types of lanthanide amide complexes, from homoleptic three- to four-coordinate, have been known for some time[2~4]. Recently, we begin to examine the utility of amide with less steric bulk, such as diphenylamide and diisopropyamide, as li- gands to synthesize homoleptic lanthanide amide complexes. For diphen…  相似文献   

5.
1 INTRODUCTION Transition metal complexes bridged by 1, 2, 4-triazole group can produce interesting structures and specific properties[1]. Many attempts have been made to synthesize a variety of complexes with paramagnetic centers by using such ligands, and their structures and magnetic properties have been characterized[2]. However, the polynuclear Ag(I) complexes bridged by 1, 2, 4-triazole have been poorly studied[3]. Recently, we have prepared a series of silver(I) triazole complex…  相似文献   

6.
Cis-dioxo-metal complex ( NH3CH2CH2NH2 ) 2.5 [ Mo0.5^(V)W0.5^(VI)O2 ( OC6H4O ) 2] 1 was obtained by the reaction of tetra-butyl ammonium hexamolybdotungstate with 1, 2-dihydroxybenzene in the mixed solvent of CH3OH, CH3CN and ethylenediamine,and characterized by X-ray diffraction, UV-vis and EPR analysis. Compared with its analogous complexes (NH3CH2CH2NH2)3[Mo^(V)O2(OC6H40)2] 2 and (NH3CH2CH2NH2)2[W^(VI)O2(OC6H4O)2] 3, the results show that tungsten(VI) is less active in redox than molybdenum (VI) and that the change of the valence induced by substitution of W(VI) for Mo(V) in EMO2(OC6H40)2]n- does not influence the coordination geometry of the complex anion in which the metal center exhibits distorted octahedral coordination with cis-dioxo catechol. The responses to EPR of complexes 1 and 2 are active but complex 3 is silent,and the UV-vis spectra exhibited by the three complexes are obvious different because of the different electronic configuration between the central Mo(V) and W(VI) ions in the complexes.It is noteworthy that complexes 1 and 2 have the similar EPR signal to flavoenzyme, suggesting that the three complexes have the same coordination geometry feature with the co-factor of flavoenzyme.  相似文献   

7.
1 INTRODUCTION It is well known that the bi-functional 4,4?-bi- pyridine (4,4?-bpy) has the ability to act as a rigid, rod-like organic building block in the self-assembly of coordination frameworks. Many researches have also been done on the metal oxalate compounds. The remarkable coordination abilities of oxalate and 4,4?- bpy ligands are applied to design and synthesize new polymeric coordination complexes[1~4] containing mixed bridging ligands. Manganese is one of the several first-r…  相似文献   

8.
1 INTRODUCTION The syntheses and structures of carboxyl complex- es have captured the interest of chemists for years due to their potential applications in many fields, such as materials, medicine, molecular electro-che- mistry and biochemistry[1~3]. So far, to the best of our knowledge, cadmium complexes with aromatic carboxylic acid as ligands have been intensively studied[4~7], but those with heterocyclic carboxylic acid as ligands are much less. α-Furoic acid is widely used in orga…  相似文献   

9.
T-jump/FT-IR spectroscopy was used to study the rapid thermal decomposition activity of [Pb2(TNR)2(CHZ)2(H2O)2]·4H2O and Cd(CHZ)2(TNR)(H2O) under 0.1 MPa Ar atmosphere. The results show that the main gaseous products of [Pb2(TNR)2(CHZ)2(H2O)2]·4H2O are NH3, H2O and HONO, while CO and NO are the major gaseous products of flash pyrolysis of Cd(CHZ)2(TNR)(H2O). Thus Cd(CHZ)2(TNR)(H2O) is not an eco-friendly and chemically compatible primary explosive. Both compounds liberate volatile metal carbonate, oxide and isocyanate compounds. The combustion temperature and products of the two compounds were calculated by Real code. The results of theoretical calculation show that the combustion temperature of [Pb2(TNR)2(CHZ)2(H2O)2].4H2O is higher than that of Cd(CHZ)2(TNR)(H2O), there is no HNCO in the combus- tion products and the amount of NO is less than the experiment result from T-jump/FTIR.  相似文献   

10.
1 INTRODUCTION 8-Quinolinolate is a very useful ligand and used to synthesize many complexes with special physical properties. For example, the complex tris(8-quinoli- nolate)aluminum(III) displays distinguished physical property in the area of electroluminescence ma- terials[1]. Based on tris(8-quinolinolate)aluminum(III), high-luminance low-voltage driven devices have been made, which opens the route to design low-cost large area displays and illuminators. The crystals thatcontain com…  相似文献   

11.
1 INTRODUCTION The design and assembly of organic-inorganic solid-state materials with active physical properties, such as materials with electrical, magnetic and opti- cal properties, has become a focus of a great deal of interest in recent years[1, 2].…  相似文献   

12.
A POMs-based 3D zeolike ionic crystal 1, {[Co(dpdo)2(CH3CN)(H2O)2]2(SiMo12O40)- (HEO)2}n (dpdo = 4,4'-bipyridine-N,N'-dioxide), was constructed via self-assembly by embedding Keggintype [SiMo12O40]^4- polyanions within the intercrystalline voids as pillars and structurally characterized. The crystal structure was determined by single-crystal X-ray diffraction. The crystal is of triclinic, space group P1 with a = 11.430(3), b = 12.242(3), c = 14.279(3)A, α = 106.196(4),β = 94.316(4), γ = 98.294(3)°, V = 1884.5(7)A^3 Z = 1, C44H50N10O54CoEMo12Si, Mr = 2880.17, Dc = 2.538 g/cm^3, p = 2.484 mm^-1,F(000) = 1388, the final R = 0.0383 and wR = 0.1096 for 7753 observed reflections with I 〉 2σ(I). Flack factor is 0.22(3). Compound 1 is a pillar-layered framework with the [SiMo12O40]^4- anions linearly located on the square voids between the 2D bilayers which are formed by the dpdo ligands and cobalt(II) ions.  相似文献   

13.
刘杰 《结构化学》1998,17(3):225-229
采用电解法制备了未见文献报道的杂多蓝H8[SiMo11Co(H2O)O39]·20H2O,通过X-射线衍射测定了其晶体结构,该晶体属单斜晶系,空间群P21;。晶胞参数全矩阵最小二乘法修正至中心原子Si与4个氧形成四面体结构,配原子M(M=11/12Mo+1/12Co)与O形成12个MO6八面体结构3个MO6共边形成4个M3O13三金属簇,4个三金属簇与SiO4四面体共角相连形成阴离子结构。  相似文献   

14.
Kinetics and Catalysis - The bimetallic MoWS2/Al2O3 catalyst was synthesized using the Keggin-type mixed heteropolyacid H4SiMo3W9O40. The monometallic catalysts SiMo12/Al2O3 and SiW12/Al2O3 based...  相似文献   

15.
Hydrogen-bonded assemblies of the two-electron reduced mixed-valence Keggin clusters [PMo(12)O(40)](5-) and [SiMo(12)O(40)](6-) were obtained by the one-pot electron-transfer reactions between p-phenylenediamine (PPD) or 2,3,5,6-tetramethyl-PPD (TMPPD) (donors) and H(+)(3)[PMo(12)O(40)](3-) or H(+)(4)[SiMo(12)O(40)](4-) (acceptors) in CH(3)CN. The redox states of the [PMo(12)O(40)](5-) and [SiMo(12)O(40)](6-) clusters were confirmed by the redox titrations and electronic absorption measurements. In (HPPD(+))(3)(H(+))(2)[PMo(12)O(40)](5-)(CH(3)CN)(3-6) (1), the N-H ~ O hydrogen-bonded interactions between the monoprotonated HPPD(+) (or diprotonated H2PPD(2+)) and the [PMo(12)O(40)](5-) resulted in a windmill-like assembly and hydrophilic one-dimensional channels are formed with a cross-sectional area of 0.065 nm(2), and these are filled by the CH(3)CN molecules. Also, the CH(3)CN molecules in salt 1 were removed by immersing the single crystals of 1 into H(2)O, CH(3)OH, and C(2)H(5)OH solvents. In the compound, (HTMPPD(+))(6)[SiMo(12)O(40)](6-)(CH(3)CN)(6) (2), the N-H ~ O hydrogen-bonded interactions between the monoprotonated HTMPPD(+) molecules and the [SiMo(12)O(40)](6-) formed a "Saturn-ring"-like assembly. Each Saturn-ring was arranged into an hexagonally packed array via hydrogen-bonded and π-stacking interactions of HTMPPD(+), while the CH(3)CN solvent present in salt 2 are only found in the zero-dimensional isolated cavities.  相似文献   

16.
高水英  曹荣  李星  林郑忠 《结构化学》2006,25(3):305-311
1 INTRODUCTION Polyoxometalates as metal-oxygen cluster ions have received a great deal of research due to their potential applications in catalysis, medicine and ma- terials science[1]. The modification of organic groups to the surface of polyoxoanions gives POMs more interesting character, and many derivatives of poly- oxoanions with organic ligands have been studied[2]. Particularly the potential applications of polyoxo- metalate as drugs in anti-viral and anti-AIDS have attracted t…  相似文献   

17.
王敬平  魏梅林  牛景杨 《化学学报》2003,61(8):1276-1280
以a-H_3PMo_(12)O_(40)·nH_2O, La_2O_3和二甲基亚砜(DMSO)为原料,在 乙腈和水的混合溶剂中制得了一维锯齿链状配位聚合物[{La(DMSO)_6(H_2O)}· (PMo_(12)O_(40))·H_2O]_n,X射线单晶衍射结果表明,聚合物中金属配阳离子与 杂多阴离子骨架通过Mo-O_d-La-O_d-Mo相连并形成一维无限链,每一个不对称结构 单元中含一个结晶水,La~(3+)的配位数为九,三帽三棱柱构型,配位氧原子分别 来自6个DMSO分子,1个H_2O分子和2个相邻杂多阴离子的端氧,晶体氧于单斜晶系 ,P2_1/c空间群,a=1.3916(3)nm,b=1.7058(3)nm,c=2.4750(5)nm,β=99.16(3)~° ,Z=4,V=5.800(2)nm~3,D_c=2.825g/cm~3,R_1=0.0446,wR_2=0.0871,IR光谱和X射线 单晶衍射结果一致表明,在固态条件下配阳离子和杂多阴离子之间存在相互作用, UV光谱表明,在稀的水溶液中,由于溶剂化作用,杂多阴离子与配阳离子处于解离 状态,热性质研究表明,形成标题化合物后,杂多阴离子的热稳定性与磷钼酸相比 明显增强。  相似文献   

18.
A novel polyoxometalate-based organic-inorganic polymer [{Ca(DMF)5}2SiMo12O40]n has been synthesized and characterized by elemental analysis, IR, UV and X-ray single-crystal structural analysis. The title compound crystallizes in a monocline lattice, P21/n, with a =1.3379(3), b = 1.9796(4), c = 1.4574(3) nm, β = 92.24(3)°, V = 3.8568(13) nm3, Z = 2, R1 = 0.083 and Rw = 0.2065. The result of crystal structure analysis indicates that Ca2+ is surrounded by seven coordination oxygen atoms with pentagonal bipyramidal geometry and bridged with terminal oxygen atom of polyanion in the structure. The compound contains an unprecedented one-dimensional linear chain built by alternate polyanions and cationic units through Mo-Od-Ca-O-Ca links in crystal. The IR spectra and X-ray crystallography analysis exhibit that there is a strong interaction between the polyanion and organic group in solid state. The electronic spectra (λ = 200-500 nm) for the title compound dissolved in the mixed solvent of acetonitrile and  相似文献   

19.
We have investigated a microwave-assisted synthesis of 4(3H)-quinazolinones by condensation of anthranilic acid, orthoesters (or formic acid) and substituted anilines,using Keggin-type heteropolyacids (H(3)PW(12)O(40).13H(2)O, H(4)SiW(12)O(40).13H(2)O,H(4)SiMo(12)O(40).13H(2)O or H(3)PMo(12)O(40).13H(2)O) as catalysts. We found that the the use of H(3)PW(12)O(40).13H(2)O acid coupled to microwave irradiation allows a solvent-free, rapid (approximately 13min) and high-yielding reaction.  相似文献   

20.
通过电化学还原的方法得到钼硅多酸的还原产物杂多蓝单晶H~8SiMo~12H~2O.测定了它的晶体结构.晶体空间群PI.a=1.3769(3)nm,b=1.4346(4)nm,c=1.4134(4)nm,a=120.47(2)°,β=110.70(2)°,γ=66.11(2)°;z=2,R=0.0608.确证杂多蓝阴离子呈现Keggin结构和与a-异构体特征,基本保持未还原杂多酸阴离子的结构.但是在结构畸变程度、键角和健长的变化以及结晶水的分布上 有明显不同.同时确定了杂多蓝阴离子结构中4个Mo^5+离子的位置.  相似文献   

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