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1.
1 INTRODUCTION Crystal engineering principles have been employ- yed in recent years to produce a variety of coordi- nation networks[1], which are of great current interest not only for their potential properties as functional solid materials[2] in host-guest chemistry, ion ex- change and catalysis, but also for their often com- plicated intriguing architectures and topologies. Ra- tional control the construction of polymeric net- works remains a great challenge in crystal engineer- ing. Mu…  相似文献   

2.
1 INTRODUCTION Supramolecular chemistry is based on the notion of creating novel structural and functional extended systems using noncovalent interactions between prefabricated molecular or ionic building blocks[1]. More recently, the design of supramolecular architec- tures by self-assembly of small building blocks has become a major research area[2, 3] due to their poten- tial applications in many fields such as selective clathration[4, 5], molecular recognition[6, 7], catalysis[8, 9] a…  相似文献   

3.
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   

4.
1 INTRODUCTION Palladium (Ⅱ) coordination and organometallic compounds usually show square planar environments at the metal center[1], and have experienced an im- portant development in the past years due to their acting as intermediates in different types of catalytic reactions and numerous applications in organic synthesis[2]. Although palladium plays an increase- ingly recognized role as a biometal[3], little is known about the structure and function of palladium compounds in living …  相似文献   

5.
1 INTRODUCTION Solid-state supramolecular chemistry and materialscience have shown quite spectacular advances overthe last two decades. At present, supramolecular che-mistry is one of the most prosperous fields in thewhole of chemistry due to their intriguing structuraldiversity and potential application as functional ma-terials, such as metallic conductivity[1], superconduc-tivity[2], non-linear optical behavior[3] and molecularmagnetism[4] invoked from the accumulation of com-posite or…  相似文献   

6.
1 INTRODUCTION During the search of molecule-based materials with interesting properties such as catalysis, cla- thration etc., much attention has been focused on the synthesis of one-, two- and three-dimensional extended solids involving cadmium[1], as its d10 configuration permits a wide variety of geometries and coordination numbers. Rigid bridged ligands such as carboxylate groups are frequently used to construct these materials. Therefore, the coordi- nation chemistry of Cd(Ⅱ) ca…  相似文献   

7.
1 INTRODUCTION Since 1,10-phenanthroline (phen) was synthe- sized at the beginning of the 19th century, phen and its metal complexes have been studied extensively. A lot of modified phen ligands (MPL)[1~5] as well as their complexes have been produced and applied in many fields, such as analytic chemistry[6], homo- genous catalysis[7] and chemical engineering[8, 9]. Now Phen and its derivatives play very important roles in supramolecular chemistry[10]. In coordina- tion chemistry, phe…  相似文献   

8.
1 INTRODUCTION Transition metal Schiff base complexes have been extensively studied in the past two decades for their various crystallographic features, enzymatic reactions, steric effects[1~4], catalysis and magnetic properties[5, 6] as well as their important role in organisms[7, 8]. Most of these first-row materials are biologically essential with a number of their complexes showing bioactivities[9, 10]. Herein we describe the synthesis and X-ray structure of the cadmium (Ⅱ) compl…  相似文献   

9.
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   

10.
1 INTRODUCTION The development of supramolecular and coordina- tion polymer complexes has recently attracted consi- derable attention due to the fundamental interest in self-assembly processes of transition-metal comple- xes, supramolecular chemistry and crystal enginee- ring[1~12]. The rational design of molecular architec- tures is essential for the creation of functional ma- terials with selective clathration[13, 14], molecular re- cognition[15, 16], catalysis[17, 18] and storage materi…  相似文献   

11.
A novel coordination polymer [Nd2(PDB)2(CH3COO)2(H2O)3] (H2PDB = pyridine3,4-dicarboxylic acid) has been synthesized by the reaction of Nd(CH3COO)3 with pyridine3,4-dicarboxylic acid under hydrothermal conditions. Elemental analysis, IR spectra and X-ray crystal structure analysis were carried out to determine the composition and crystal structure of the title complex which belongs to the triclinic system, space group P^-1 with a = 6.9409(14), b = 7.5497(15), c = 22.530(5)A, α = 84.79(3), β = 88.15(3), γ= 75.55(3)^o, C18H18N2O15Nd2, Mr = 790.82, Z = 2, V = 1138.5(4) A^3, Dc = 2.307 g/cm^3,μ = 4.593 mm^-1, -6≤h≤8, -5≤k ≤8, -26≤l≤ 26, F(000) = 760, Rint = 0.0298, R= 0.0314 and wR= 0.0695 (I〉 2σ(I)). Nd(1) and Nd(2) are linked into zigzag chains by carboxylate groups of acetate with interesting μ3-η^2:η^2 fashion. The zigzag chains are bridged by PDB to form a 2D framework, and a 3D supramolecular network is further constructed via π-π stacking.  相似文献   

12.
H_(3+n)[AsMo_(12-n)V_nO_(40)]·9H_2O(n=2—4)的结构   总被引:3,自引:1,他引:3  
邓谦  黄幼青 《结构化学》1993,12(6):430-436
X光晶体结构分析证实H_(3+n)[AsMo_(12-n)V_+nO_(40)]·9H_2)(n=2—4)的晶体同构,空间群为P,Z=2。n=2时,a=13.951(5),b=14.137(5),c=13.556(4),α=112.44(2),β=109.49(3),γ=60.77(3)°,V=2120.2,M_r=1943.36,D_c=3.044g.cm~(-3),μ=40.90cm~(-1),F(000)=1828。用6216个I>3σ(I)的独立衍射精修结构,R=0.082;n=3时,a=13.891(7),b=14.076(5),c=13.483(5)A,α=112.34(3),α=109.26(3),γ=60.82(3)°,V=2094.5,M_r=1899.37,D_c=3.011g.cm~(-3),μ=40.63cm~(-1),F(000)=1792。用6699个I>3σ(I)的独立衍射精修结构,R=0.054;n=4时,a=13.854(3),b=14.099(2),c=13.501(4),α=112.09(2),β=109.13(2),γ=61.03(2)°,V=2103.0,M_r=1855.38,D_c=2.92(悬浮法),D_c=2.930g.cm~(-3),μ=39.71cm~(-1),F(000)=1756。用7613个I>3σ(I)的独立衍射精修结构,R=0.044。实验采用MoKα辐射,λ=0.71073,T=296K。杂多阴离子均呈准Keggin结构,12个金属原子呈无序分布,可以M(Mo/V)表示。AsO_4四面体中As—O键长1.66—1.68,O—As—O键角均在109.5°左右。畸变的MO_6八面体中,M—O键长分布在1.63—2.36范围。水分子无序处在晶胞中十四个位置上,除O_w(12)和O_w(13)外的水分子均与杂多阴离子形成氢键,且水分子间形成如沸石中那样的复杂?  相似文献   

13.
1 INTRODUCTION The polydentate ligand nitrilotripropionic acid, H3ntp[N(CH2CH2COOH)3], has attracted conside- rable research interest in constructing coordination polymers, designing organic-inorganic hybrid mate- rials[1], synthesizing supramolecular compounds[2], etc. due to its high degree of flexibility with three carboxylic acid moieties allowing for a variety of coordination through oxygen atoms[3]. It also pro- vides other versatile properties such as the possibili- ty of inter-…  相似文献   

14.
1INTRODUCTIONRecently,therehasbeenconsiderableinterestinthelanthanide(III)hexacyanoferrates,theanalogoushexacyanocobaltateandhexacyanochromiumatecom-plexesbecauseoftheirpotentialapplicationsascata-lyticandsemi-conductivematerials.InitialstudiesofmetalhexacyanocobaltateswerecarriedoutbyJa-mesandWilland[1]whoreportedtheamountofhy-drationassociatedwithmicroscopiccrystalsofsever-allanthanidecomplexes.FurtherBonnetandParis[2]studiedtheLNCo(CN)6?nH2Oseries(n=4)byusinginfraredandX-raymethod…  相似文献   

15.
The crystal structure of the new title compound 2-ethoxy-3-n-butyl- benzofuro[2,3d]pyrimidin-4(3H)-one (C16H18N2O3, Mr = 286.32) has been prepared and determined by singlecrystal X-ray diffraction. The crystal is of monoclinic, space group P21/c with a = 13.7167(14), b = 13.113(1), c = 8.378(1) A, β = 98.992(2)^o, V = 1488.4(3) A^3, Z = 4, Dc = 1.278, F(000) = 608, μ = 0.089 mm^-1, MoKa radiation (2 = 0.71073), R = 0.0498, wR = 0.1238 for 2336 observed reflections with I 〉 2σ(I). X-ray diffraction analysis reveals that all ring atoms in the benzo[4, 5]furo [2,3-d] pyrimi- dinone moieties are almost coplanar.  相似文献   

16.
The reaction of VO(acac)2 with 2-hydroxyl-1-naphthaldehyde isonicotinyl hydrazone and amines (ethylenediamine or diethylenetriamine) in CH3OH yields crystals of novel vanadium compounds characterized by IR, NMR spectroscopic methods and X-ray single-crystal structure determination. Two different vanadium units exist in the crystal cell of [VO2(C17H11N3O2)][VO- (C4H13N3)(C6H5N3O)](C2H5OH) which crystallizes in the triclinic system, space group P1 with a = 8.0104(17), b = 13.898(3), c = 14.955(3)A, α = 89.103(4), β = 79.551(4), γ = 78.352(4)°, V = 1603.3(6)A^3, Mr = 723.54, Dc = 1.499 g/cm^3, Z = 2, λ(MoKα) = 0.71073 ]A,μ= 0.644 mm^-1, F(000) = 748, the final R = 0.0547 and wR = 0.0997 for 8920 observed reflections with I 〉 2σ(I). According to structure analysis, two different molecules are arranged in the lattice and the two vanadium atoms adopt octahedral and square pyramidal coordination geometries, respectively. The interactions between DNA and vanadium complexes have been investigated by UV-Vis absorption spectro- photometry.  相似文献   

17.
A novel coordination polymer [Sm(4-Pyta)3(H2O)2]n has been synthesized by the hydrothermal reaction between 4-Pyta (4-Pyta = 4-pyridylthioacetate) and Sm(NO3)3. The structure was characterized by elemental analysis, IR spectra and single-crystal X-ray diffraction. The crystal belongs to the triclinic system, space groupP1, with a = 9.100(2), b = 11.842(3), c = 12.183(3) A, α= 79.781(4), β= 74.124(4), γ = 841882(5)^o, V = 1241.6(5) A^3, Z = 2, Mr = 690.95, Dc = 1.84806 g/cm^3, F(000) = 686,μ = 2.669 mm^-1, the final R = 0.0388 and wR = 0.0808 for 4149 observed reflections with I 〉 2σ(I). The structural analysis shows that the complex exhibits a one-dimensional architecture. Intermolecular hydrogen bonding interactions are found in the complex molecules.  相似文献   

18.
SynthesisandCrystalStructureofaMixed-ValenceTrinuclearManganeseComplex:Mn_3O(O_2CPh)_6(Py)_3XuHao;LiJin-Yu;LiuQi;XuZheng;YouXia...  相似文献   

19.
1 INTRODUCTION Polyoxometalates, a rich and remarkable classof inorganic cluster system[1], exhibit diverse appli-cation possibilities due to their topological and elec-tronic properties, ranging from their well-known roleas reagents in analytical, b…  相似文献   

20.
The title compound (C26H20ClN3O3) has been synthesized by 1,3-dipolar cycloaddition reaction from isatin, sarcosine and (Z)-4-(4-chlorobenzylidene)-2-phenyloxazol-5(4H)-one through a one-pot procedure, and its structure was confirmed by IR, IH NMR, elemental analysis and single-crystal X-ray diffraction analysis. The crystal belongs to the triclinic system, space group PI, with a = 9.3903(19), b = 11.398(2), c = 12.603(3) A, α = 83.495(3), β = 68.988(3), γ = 67.178(3)^o, V= 1160.1(4)A^3 Z = 2, Mr= 457.90, Dc= 1.311 g/cm^3, p = 0.198 mm ^-1, F(000) = 476, the final R = 0.0489 and wR = 0.1144 for 3109 observed reflections with I 〉 2σ(I).  相似文献   

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