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1.
1 INTRODUCTION Recently, the researches on inorganic-organic hy-brid compounds represent an advanced field in mate-rial science[1]. At the molecular level, the combina-tion of two extremely different components providesan avenue to design new hybrid materials as well asthe ability to modulate properties of one or more ofthe components[2~6]. Some attractive properties, suchas efficient luminescence[2~4], ideal thermal and me-chanical stability, interesting magnetic[5], non-linearoptical[…  相似文献   

2.
1 INTRODUCTION As a thiolate ligand with potential S and N donors, thiourea is interesting due to its multifunctional coor-diation modes (unidentate-N, unidentate-S or biden- tate-N, S)[1]. As a good extracting agent for nobelme-tals[2], thiourea has…  相似文献   

3.
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   

4.
1 INTRODUCTION The synthesis of chiral clusters containing four different atoms at the vertexes of the tetrahedron has been extensively studied because the chiral cluster can induce an asymmetric catalysis potentially[1]. Until now, many tetrahedron-type chiral clusters have been reported, but only a few of the reactions about the organic group in these clusters were investi- gated[2~4]. In this paper, we described the syntheses of clusters 3 and 4, and the structure of the former. 2 …  相似文献   

5.
1 INTRODUCTION In recent years, the rational design and synthesisof metal-directed supramolecular frameworks throughintermolecular hydrogen bonds, π-π stacking interac-tion or other weak interactions have received muchattention because of their interesting molecular topo-logies and various potential applications in catalysis,superconductor, magnetism, nonlinear optics, sen-sors and molecular recognition[1~4]. On the otherhand, the attachment of mono- or polypyridyl frag-ments to a ferr…  相似文献   

6.
1 INTRODUCTION Palladium compounds have attracted much attention as a consequence of their application in homogeneous and heterogeneous catalyses[1]. For instance, palladium compounds are the most active catalysts for the carbonylation, such as palladium-catalyzed carbonylation of nitroarenes, aryl halides, alkyne and so on[2~4]. Some dramatic results in the homogeneous catalysis of the reactions of organic compounds, particularly the successful commercial exploitation of the Wacker on…  相似文献   

7.
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   

8.
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   

9.
1 INTRODUCTION It has been known that the electron correlation energy of molecular systems was, and still is, one of the most serious bottleneck problems to the chemis- try accuracy of computational quantum chemistry. Since L鰓din[1] gave the definition …  相似文献   

10.
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   

11.
用乙二胺作模板剂在水热条件下合成出一个新的三维开放骨架结构的亚磷酸铟[In2(HPO3)4]·(NH3CH2CH2NH3)(1), 并对其晶体结构进行了测定和表征.  相似文献   

12.
采用水热合成法以丁二胺作为模板剂合成了钴的有机二膦酸超分子化合物[NH3(CH2)4NH3]Co(hedpH2)2(H2O)2 [hedpH4 = 1-羟亚乙基二膦酸, CH3C(OH)(PO3H2)2]。用元素分析、红外光谱、紫外-可见光谱、热重分析以及单晶结构解析对其进行了表征。该化合物的化学式为:C8H30N2CoO16P4,Mr = 593.15,晶体属单斜晶系,空间群C2/c,晶胞参数a = 16.128(2), b = 12.427(1), c = 12.610(2) ? b = 121.389(9), V = 2157.3(4) 3, Z = 4, Dc = 1.826 g/cm3, m(MoKa) = 1.172 mm-1, F(000) = 1228。结构用直接法解出,最终偏离因子R = 0.0285, wR = 0.0747。该化合物的结构包含单核的Co(hedpH2)2- 阴离子,阴离子之间通过氢键连结形成具有空隙的三维超分子骨架结构,双质子化的丁二胺分子位于空隙中。  相似文献   

13.
Introduction Over the past decades, polyoxometalates(POMs)have been attracting extensive interestowing to the widerange of their topological properties and potential appli-cations in catalysis, photochemistry, electrochromism,and magnetism[1,2]. Meanwhile, owing to the potentialapplication of polyoxometalaes as anticancer and antivi-ral drugs, their complexes have attracted increasing in-terest of both inorganic chemists and biochemists[3]. Itis well known that polyoxometalates are excellent …  相似文献   

14.
Song HH  Zheng LM  Wang Z  Yan CH  Xin XQ 《Inorganic chemistry》2001,40(19):5024-5029
Four new zinc diphosphonate compounds with formulas [NH(3)(CH(2))(2)NH(3)]Zn(hedpH(2))(2).2H(2)O, 1, [NH(3)(CH(2))(n)()NH(3)]Zn(2)(hedpH)(2).2H(2)O, (n = 4, 2; n = 5, 3; n = 6, 4) (hedp = 1-hydroxyethylidenediphosphonate) have been synthesized under hydrothermal conditions at 110 degrees C and in the presence of alkylenediamines NH(2)(CH(2))(n)()NH(2) (n = 2, 4, 5, 6). Crystallographic data for 1: monoclinic, space group C2/c, a = 24.7422(15), b = 5.2889(2), c = 16.0338(2) A, beta = 117.903(1) degrees, V = 1856.17(18) A(3), Z = 4; 2: monoclinic, space group P2(1)/n, a = 5.4970(3), b = 12.1041(6), c = 16.2814(12) A, beta = 98.619(5) degrees, V = 1071.07(11) A(3), Z = 2; 3: monoclinic, space group P2(1)/n, a = 5.5251(2), b = 12.5968(3), c = 16.1705(5) A, beta = 99.182(1) degrees, V = 1111.02(6) A(3), Z = 2; 4: triclinic, space group P-1, a = 5.4785(2), b = 14.1940(5), c = 16.0682(6) A, alpha = 81.982(2) degrees, beta = 89.435(2) degrees, gamma = 79.679(2) degrees, V = 1217.11(8) A(3), Z = 2. In compound 1, two of the phosphonate oxygens are protonated. The metal ions are bridged by the hedpH(2)(2-) groups through three of the remaining four phosphonate oxygens, forming a one-dimensional infinite chain. The protonated ethylenediamines locate between the chains in the lattice. In compounds 2-4, only one phosphonate oxygen is protonated. Compounds 2 and 3 have a similar three-dimensional open-network structure composed of [Zn(2)(hedpH)(2)](n) double chains with strong hydrogen bonding interactions between them, thus generating channels along the [100] direction. The protonated diamines and water molecules reside in the channels. Compound 4 contains two types of [Zn(2)(hedpH)(2)](n) double chains which are held together by strong hydrogen bonds, forming a two-dimensional network. The interlayer spaces are occupied by the [NH(3)(CH(2))(6)NH(3)](2+) cations and water molecules. The significant difference between structures 2-4 is also featured by the coordination geometries of the zinc atoms. The geometries of those in 2 can be described as distorted octahedral, and those in 3 as distorted square pyramidal. In 4, two independent zinc atoms are found, each with a distorted octahedral and a tetrahedral geometry, respectively.  相似文献   

15.
A new cobalt(II) carboxylate-phosphonate, namely, Co[HO2C(CH2)3NH(CH2PO3H)2]2, with a layered architecture has been synthesized by hydrothermal reactions. The Co(II) ion in the title compound is octahedrally coordinated by six phosphonate oxygen atoms from four carboxylate phosphonate ligands. Neighboring CoO6 octahedra are interconnected by phosphonate groups into a 2D layer with a 4,4-net topology. Adjacent layers are further cross-linked via hydrogen bonds between the noncoordinate carboxylate groups and noncoordinate phosphonate oxygens. The ac and dc magnetic susceptibility and magnetization measurements indicate that Co[HO2C(CH2) 3NH(CH2PO3H)2]2 is a canted antiferromagnet with T(c) = 8.75 K.  相似文献   

16.
在含有HF的体系中, 用乙二胺作模板剂, 通过水热方法合成了一个新的三维亚磷酸铟[In4(HPO3)7(H2O)3](NH3CH2CH2NH3)·(H2O), 并对其进行了红外光谱、热重、ICP和CHN元素分析等表征. 单晶X射线衍射分析结果表明, 该化合物属于三方晶系, P3空间群, 晶胞参数a=1.37883(7) nm, c=0.93450(9) nm, V=1.53862(2) nm3, Z=2, Dc=2.489 Mg/m3, 最终一致性因子R1[I >2σ(I)]=0.0526, wR2[I>2σ(I)]=0.1328, GOF=1.082. 其结构中的InO6八面体、InO5(H2O)八面体和HPO3假四面体通过O原子共顶点连接, 分别沿a, b轴方向形成含有十二元环的交叉孔道, 客体水分子和双质子化的乙二胺分子存在于孔道中.  相似文献   

17.
A new cluster {Mo3S4[NH2CH2CH(O)CH2NH2]3}(DTP)·(H2O)2·(DMF) (DTP = diethyldithiophosphate) has been synthesized via ligand substitution reaction of Mo3S4(DTP)4(H2O) with an alkaline ligand 1,3-diamino-2-propanol(DAPROH) in a mixed organic solvent, and its crys- tal structure was determined with the following data: Mo3S6PC16H48O8N7, Mr = 977.76, triclinic, space group P, Z = 2, a = 10.319(2), b = 12.843(3), c = 15.335(3)(A), α = 65.26(3), β = 82.18(3), γ = 70.67(3)o, V = 1741.7(6) (A)3, Dc = 1.864 g/cm3, μ = 1.517 mm-1, F(000) = 988, the final R = 0.0794 and wR = 0.2111 for 6318 observed reflections (I>2σ(I)). The structure analysis indicates that all DTP ligands of Mo3S4(DTP)4(H2O) are replaced and each DAPRO molecule acts as a tri- dentate ligand chelating to each Mo atom of the Mo3S4 core. Different from the precursor, the clus- ter symmetry is elevated to C3. In addition, the UV-spectrum of the title compound was measured.  相似文献   

18.
The structure of N,N-dimethylethylenediammonium pentachloroantimonate(III), [(CH3)2NH(CH2)2NH3][SbCl5], NNDP, was investigated at 100 and 15 K at ambient pressure, as well as at pressures up to 4.00 GPa at room temperature in the diamond-anvil cell. The stable structure at low temperatures and low pressures consists of isolated [SbCl5]2- anions and [(CH3)2NH(CH2)2NH3]2+ cations. The inorganic anions have a distorted square pyramidal geometry. They are arranged in linear chains parallel to the c axis. In contrast to the low-temperature studies, where no phase transition was detected, pressure induces a P2(1)/c --> P2(1)/n phase transition between 0.55 and 1.00 GPa, accompanied by a doubling of the a unit-cell parameter. This solid-solid transition results from changes in the electron configuration of the Sb(III) atom and formation of the Sb-Cl bridging bonds between inorganic polyhedra to form, at approximately 1.0 GPa, isolated [Sb2Cl10]4- units consisting of [SbCl6]3- octahedra and [SbCl5]2- square pyramids connected by a common corner. The intermolecular distances continuously decrease with further increase in pressure, and at approximately 3.1 GPa, zigzag [{SbCl5}n]2n- chains containing corner-sharing [SbCl6]3- octahedra are formed. The unit-cell volume of NNDP decreases by 18.15% between room pressure and 4.00 GPa. The linear distortions of the [SbCl5]2- and [SbCl6]3- polyhedra decrease with increasing pressure and decreasing temperature and indicate a reduction in the stereochemical activity of the lone electron pair on the Sb(III) atom.  相似文献   

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