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1.
1mTh0DUCTIONHeteropolycomp1exespossessalotofdistinctivecharacteristicsasmolecularm0delofcatalystdesign"'.Considerableattentionhasbeengiventothecrystalstruc-turesofheteropolycomplexescontainingdifferentcomponents,andmanyofthecrystalstructuresofthesec0mplexeshavebeendetermined.Wereportedprevious1ythecrystalstructureoftheheteropolyc0mplexeswithlanthanide,inwhichtw0kindsofelementsarecontainedinthemonolacunaryheteropolyligand".",theorientationsoftheminthecrystalareordered.Inthispaper,thecrystals…  相似文献   

2.
Recently, Many tri-component heteropoly compounds have been synthesized, but tetra-component heteropoly compounds have not been reported. It is known that mixtures of Mo and Co oxides are a promoted hydrodesulphurization catalyst. The title compound is a polyoxophosphate containing Mo, Co and W, the divalent anion possesses two-fused Keggin structure, whereas MoO_6 has been confirmed to be an elementary structure unit of isopoly and heteropoly molybdates, but it, as an idependent anion, has not been reported either.  相似文献   

3.
1 INTRODUCTION Though the investigation on chemistry of tran- sition metal-peroxy complexes has been extensively carried out, up to now, only four structures of purely inorganic dimeric peroxovanadates have been deter- mined by single-crystal X-ray meth…  相似文献   

4.
标题化合物是通过四硫代钨酸铵和柠檬酸钾反应而得。用IR、XPS、元素分析进行了结构表征,X-ray结构测定进一步肯定了以上结论。该晶体为三斜晶系,P1空间群,晶胞参数为:a=0.85111(9)nm,b=0.9784(10)nm,c=1.082(11)nm,α=114.85(12)°,β=106.58(11)°,γ=98.89(10)°,Z=1,V=0.7436(13)nm3,Dc=2.594g/cm3,F(000)=554,μ=86.61cm-1,一致性因子R=0.075,WR2=0.1889。  相似文献   

5.
1INTRODUCTIONHeteropolycompoundsareacidsaswellasoxidizingagents"'.Takingadvantageoftheseproperties,heteropolycompoundshavebeenusedascatalystsforvarioussyntheticreaction(bothinhomogeneousandheterogeneoussystems).Hydrationofpropeneinaliquidphasecatalyzedbyheteropolyacidshasbecomeacommercializedprocess.Oxidationofmethacroleinorisobutyricacidtoproducemethacrylicacidisanexampleofindustrialprocessestowhichthesecompoundsareapplied"--'>.Theoxidationpotential(oroxidizingability)decreaseslinearlywi…  相似文献   

6.
1 INTRODUCTION In the last decade, cyano-bridged Prussian Blueanalogues[1] have been intensively studied from theviewpoint of application as functionalized molecule-based magnets[2], chemical sensor materials[3], fluo-rescent materials[4] and zeolitic-type materials[5, , 6]etc. In 1976, a series of cyano-bridged three-dimen-sional rare earth hexacyanometalates(IIILnM(CN)6?nH2O (M = Fe or Cr, n = 4 or 5) were crystallized andsubjected to single-crystal X-ray analysis[7]. …  相似文献   

7.
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   

8.
1 INTRODUCTIONCertaincoppercomplexeshavebeenshowntohaveunusualchemicalpropertiessuchasoxygentransfer,oxidativeadditionandhomogenouscatalytichydrogenation[1].Oxidativeadditionreactionsarekeystepsintheactivationofσbondsinagreatnumberofcatalyticprocess.Cop…  相似文献   

9.
10.
李宝龙  徐艳  刘琦  王化勤  徐正 《中国化学》2002,20(2):187-190
IntroductionCrystalengineeringofsupramoleculararchitecturessustainedbycoordinatecovalentbondsorhydrogenbondsrepresentsarapidlyexpandingfieldthatofferspo tentialfordevelopmentofnewclassesoffunctionalsolids .1,2 Thearchitecturesofcoordinationpolymerscanbe…  相似文献   

11.
A novel complex [Pb(qina)2(DMSO)]·H2O was synthesized,of which qina-is the quinaldic acid radical and DMSO the dimethyl sulfoxide. Elemental analysis,IR spectra,and X-ray single-crystal diffraction were carried out to determine the composition and crystal structure. This complex belongs to monoclinic system,space group P121/n1,with a=7.1553(17),b=17.543(2),c=17.306(2) ,β=91.671(4)°,C22H20N2O6PbS,Mr=647.65,Z=4,V=2171.5(6) 3,Dc=1.981 g/cm3,μ=7.908 mm-1,F(000)=1248,–9≤h≤6,–23≤k≤19,–22≤l≤22,R=0.0221 and wR= 0.0488. Weak coordinate bond is formed between oxygen atom in DMSO and Pb(Ⅱ ) . There are also weak interactions,such as π-π interaction,hydrogen bonds and so on,among the complex molecules.  相似文献   

12.
1 INTRODUCTION In recent years, cyano-bridged heterometallic coordination compounds have inspired remarkable attention due to their rich and interesting structures and magnetic behaviors. However, these studies were mainly focused on the transition metals. Although several unusual cyanide bridging lanthanide-transition metal complexes have been re- ported[1~6], this field continuously possesses tre- mendous researching potentialities. As regardsPrussian Blue lanthanide complex, divers…  相似文献   

13.
1 INTRODUCTION Polyoxometalates are the unique metal-oxygen clusters composed of transition metals in groups V and VI (Mo, W, V, Nb, Ta) in a high oxidation state showing a large structural varieties as well as inte- resting physical and chemical properties in diverse fields including catalysis, analytical chemistry, nanotechnology, chemical sensing, biochemical and geochemical processes, medicine and materials science[1~5]. Recently, there has been increasing interest in the synthesis…  相似文献   

14.
1 INTRODUCTION In recent years, extensively attention has been fo- cused on the design and synthesis of d10 metal- based complexes[1, 2]. A series of d10 metal-organic frame- works have been described not only because of their intriguing structures but also due to their ptential ap- plications in photoluminescent fields[3~7]. Although phthalate ligand was successfully used to design and synthesize a wide variety of metal complexes, those containing Cd(II) complex are less considered[8~…  相似文献   

15.
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   

16.
Hybrid organic-inorganic compounds have attracted increasing interest in recent years due to the possibility of combination of different characteristics of the compounds to get unusual structures, properties, or applications1. Polyoxometalates (POMs) whic…  相似文献   

17.
1 INTRODUCTION The polyoxoanion-based inorganic and organo- metallic complexes, especially isopolymolybdates, have attracted considerable interest for their appli- cations in catalysis, sorption, clathration, magnetism and photochemistry[1]. Octamoly…  相似文献   

18.
A novel complex,[Mn(C_6H_(12)N_4)_2(H_2O)_4][Mn(H_2O)_6][SO_4]_2·6H_2O,was synthesized and hexagonal single crystals with centimeter-scale sizes were obtained by the method of solvent evaporation.It was characterized by elemental analysis,infrared spectrum,thermogravimetric analysis and X-ray single-crystal diffraction.The complex belongs to triclinic crystal system,space group P■ with a=9.3390(8),b=13.3520(13),c=16.3207(13)?,α=100.7160(3)°,β=90.1020(10)°,γ=109.9490(5)°,V=1874.9(3)?~3,Z=2,D_c=1.542 g/cm~3,M_r=870.64,μ=0.876 mm~(-1),T=293(2) K,F(000)=916 and S=0.990.The crystal structure determination displayed a distorted octahedral geometry around the manganese atom,which is bound to two nitrogen atoms from hexamethylenetetramine,acting as monodentate ligands,and to four aqua ligands.Variable-temperature magnetic measurements of the complex indicate the presence of weak antiferromagnetic interaction between manganese centers.  相似文献   

19.
A new mononuclear Co(II) complex, [Co(hmz)2(H2O)4]·2H2O, has been synthesized by the reaction of Co(CH3COO)2·4H2O with 1-(4-hydroxyphenyl)-5-mercaptotetrazole (Hhmz). It crystallizes in the monoclinic system, space group P21/n with a = 13.502(5), b = 6.718(3), c = 13.972(6) , β = 117.532(4)o, V = 1123.9(8) 3, Z = 2, M r = 553.45, F(000) = 570, Dc = 1.635 g/cm3, μ = 1.008 mm–1, the final R = 0.0272 and wR = 0.0684 for 2194 observed reflections (I > 2σ(I)). The Co(II) is six-coordinated by two nitrogen atoms from two hmz–1 ligands and four water molecules, forming an octahedral geometry. The intermolecular hydrogen bonding and offset-panel π-π stacking interactions between the adjacent molecules extend the compound into a three- dimensional supramolecular framework. The title compound emits strong blue fluorescent light (λem(max) = 427 nm) at room temperature and is red-shifted compared with free ligand Hhmz (λem(max) = 342 nm).  相似文献   

20.
1 INTRODUCTION Recently, the ternary or quaternary mixed anion complexes of cerium(III) containing 1,10-phenanthroline (phen) have attracted considerable attention due to their rich structural chemistry and appealing magnetic properties[1]. Panagiotopou…  相似文献   

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