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近年来 ,微孔配位聚合物的研究越来越引起人们的重视 .与传统的微孔材料硅酸盐、硅铝酸盐、磷铝酸盐等相比 ,微孔配位聚合物具有独特的优势 :一方面 ,可以将金属离子所特有的磁学、光学、电学和氧化 -还原等特性引入所设计合成的配位聚合物中 ;另一方面 ,有机配体的多样性、可修饰性和与各种金属离子的不同组合 ,为设计合成尺寸可控、形状可控和性质可控的各种配位聚合物提供了可能 .因此 ,微孔配位聚合物在分子磁性、分子识别、信息储存、分离、催化和非线性光学等方面有着广泛的应用前景 .于是 ,设计和合成微孔配位聚合物成为当前具有挑战… 相似文献
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以类雌性激素双酚A为模板分子,选取4-乙烯基吡啶作为功能单体,在极性溶剂甲醇中,通过非共价键完成自组装过程,沉淀聚合制备对双酚A分子具有高度选择性识别和亲和力的分子印迹聚合物.采用紫外-可见光谱研究了双酚A和4-乙烯基吡啶的配合方式以及配位比,结果表明双酚A与4-乙烯基吡啶以配位比1∶2的方式,在极性溶剂中,无法以常用的氢键形成超分子配合物,却可以π-π堆积这种非共价键完成自组装过程.通过红外谱图,验证了沉淀聚合法制备的印迹聚合物可以完成双酚A的印迹和可逆分离.通过扫描电镜和等温吸附实验考察了分子印迹聚合物对模板分子的特异性识别和选择性吸附机理,印迹聚合物的特异性吸附容量为37.39μmol/g,印迹指数为4.31;对其结构类似物四溴双酚A和苯酚的分离因子分别为2.51和2.06,同时对莠去津,萘普生和槲皮素的分离因子分别为2.14,2.26和2.63,证实了分子印迹聚合物在极性溶剂中可以对双酚A分子进行很好的特异性识别,并且识别环境更接近天然分子环境. 相似文献
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近年来,微孔配位聚合物的研究越来越引起人们的重视.与传统的微孔材料硅酸盐、硅铝酸盐、磷铝酸盐等相比,微孔配位聚合物具有独特的优势:一方面,可以将金属离子所特有的磁学、光学、电学和氧化-还原等特性引入所设计合成的配位聚合物中; 相似文献
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以碱式碳酸铜和四氮唑乙酸在水中反应制备得到四唑乙酸铜(Ⅱ)含能配位聚合物[Cu(tza)2]n,并培养出单晶.运用元素分析、FHIR分析和X射线单晶衍射对含能配位聚合物的组成和结构进行了表征,采用差示扫描量热分析( DSC)和热重,微分热重分析(TG-DTG)研究了含能配位聚合物的热分解过程,结果表明,[Cu(tza)... 相似文献
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以[Ni(CN)4]2-为构筑基元,与过渡金属离子Mn2+通过溶液缓慢扩散法合成出二维Hofmann类氰基桥联配位聚合物Mn(H2O)2[Ni(CN)4]·4H2O(1),并解析了其晶体结构.配位聚合物1属正交晶系,空间群Cmcm,晶胞参数a=0.73080(5)nm,b=1.21372(8)nm,c=1.40875(9)nm,α=β=γ=90°,Ni和Mn中心通过氰桥交互连接构成二维波浪形层状结构.通过混合法得到系列Hofmann类配位聚合物M(H2O)2[Ni(CN)4]·xH2O(M=Mn,Fe,Co,Ni,Cd)的粉末样品,粉末XRD结果表明,系列配位聚合物具有与1相同的晶体结构;变温粉末XRD和热重分析结果表明,系列配位聚合物具有较高的热稳定性.以Mn(H2O)2[Ni(CN)4]·xH2O的脱水样品为构筑模块与柱状配体pyrazine组装构筑的三维多孔配位聚合物具有一定的储气性能. 相似文献
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钴、镍-氨基三乙酸配位聚合物Na[M(nta)]·H2O(M=Co,Ni)的水热合成、结构与磁性 总被引:1,自引:0,他引:1
由有机配体同金属离子作用构建的配位聚合物具有与无机微孔晶体类似的空旷骨架结构,并在非线性光学材料、磁性材料、超导材料及催化等诸多方面具有潜在的应用前景[1~4].在配位聚合物的合成中,配体的种类不仅直接影响到聚合物的合成,而且还涉及到聚合物的结构维数[5~7].目前,用来构建这些配合物的有机配体大多数都带有相同的可配位基团,较少应用具有两种以上的配位基团的有机配体.本文采用同时含有氮和氧两种配位原子的多齿配体氨基三乙酸[8~12],在水热条件下分别以Co2+和Ni2+作为组装基元,通过自组装合成了具有三维骨架结构的Na[M(nta)]·H2O [M=Co(1),Ni(2)]配位聚合物,并进行了结构与磁性研究. 相似文献
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Martin Sahlberg Yvonne Andersson 《Acta Crystallographica. Section C, Structural Chemistry》2009,65(3):i7-i8
Scandium magnesium gallide, Sc2MgGa2, and yttrium magnesium gallide, Y2MgGa2, were synthesized from the corresponding elements by heating under an argon atmosphere in an induction furnace. These intermetallic compounds crystallize in the tetragonal Mo2FeB2‐type structure. All three crystallographically unique atoms occupy special positions and the site symmetries of (Sc/Y, Ga) and Mg are m2m and 4/m, respectively. The coordinations around Sc/Y, Mg and Ga are pentagonal (Sc/Y), tetragonal (Mg) and triangular (Ga) prisms, with four (Mg) or three (Ga) additional capping atoms leading to the coordination numbers [10], [8+4] and [6+3], respectively. The crystal structure of Sc2MgGa2 was determined from single‐crystal diffraction intensities and the isostructural Y2MgGa2 was identified from powder diffraction data. 相似文献
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Marina I. Naumova Natalia V. Kuratieva Nina V. Podberezskaya Dmitry Yu. Naumov 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(5):i53-i55
The structures of the hypophosphites KH2PO2 (potassium hypophosphite), RbH2PO2 (rubidium hypophosphite) and CsH2PO2 (caesium hypophosphite) have been determined by single‐crystal X‐ray diffraction. The structures consist of layers of alkali cations and hypophosphite anions, with the latter bridging four cations within the same layer. The Rb and Cs hypophosphites are isomorphous. 相似文献
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Paul-Louis Fabre Dominique de Montauzon René Poilblanc 《Transition Metal Chemistry》1987,12(5):434-440
Summary The ability of [MoS4]2–, anions to be used as ligands for transition metal ions has been widely demonstrated, especially with Fe2+. The present study has been restricted to linear complexes such as (NEt4)2 [Cl2FeS2MoS2] and (NEt4)2[Cl2FeS2MoS2FeCl2]. Their electrochemical properties are described: upon electrochemical reduction, these compounds yield MoS2, as a black precipitate, and an iron complex in solution, assumed to be [SFeCl2]2–. The electrochemical reduction goes through two electron transfers, coupled with the breakdown of the molecular skeleton: a DISPl and an ECE mechanism. Depending on the solvent, the following equilibrium may be observed: [Cl4Fe2MoS4]2–[Cl2FeMoS4]2–+FeCl2. The equilibrium constant, KD, was evaluated by differential pulse polarography. KD is tightly related to the donor number of the solvent. 相似文献
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On Dialkali Metal Dichalcogenides β-Na2S2, K2S2, α-Rb2S2, β-Rb2S2, K2Se2, Rb2Se2, α-K2Te2, β-K2Te2 and Rb2Te2 The first presentation of pure samples of α- and β-Rb2S2, α- and β-K2Te2, and Rb2Te2 is described. Using single crystals of K2S2 and K2Se2, received by ammonothermal synthesis, the structure of the Na2O2 type and by using single crystals of β-Na2S2 and β-K2Te2 the Li2O2 type structure will be refined. By combined investigations with temperature-dependent Guinier-, neutron diffraction-, thermal analysis, and Raman-spectroscopy the nature of the monotropic phase transition from the Na2O2 type to the Li2O2 type will be explained by means of the examples α-/β-Na2S2 and α-/β-K2Te2. A further case of dimorphic condition as well as the monotropic phase transition of α- and β-Rb2S2 is presented. The existing areas of the structure fields of the dialkali metal dichalcogenides are limited by the model of the polar covalence. 相似文献
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[reaction: see text] Fluoranthene 2 and heptacycle 3 are easily accessible from the reaction of diyne 1 and norbornadiene (NBD) in the presence of the rhodium catalyst. The unusual [(2+2)+(2+2)] adduct 3 was confirmed by the X-ray crystal structure analysis. 相似文献
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[(n‐Bu)2Sn(O2PPh2)2] ( 1 ), and [Ph2Sn(O2PPh2)2] ( 2 ) have been synthesized by the reactions of R2SnCl2 (R=n‐Bu, Ph) with HO2PPh2 in Methanol. From the reaction of Ph2SnCl2 with diphenylphosphinic acid a third product [PhClSn(O2PPh2)OMe]2 ( 3 ) could be isolated. X‐ray diffraction studies show 1 to crystallize in the monoclinic space group P21/c with a = 1303.7(1) pm, b = 2286.9(2) pm, c = 1063.1(1) pm, β = 94.383(6)°, and Z = 4. 2 crystallizes triclinic in the space group , the cell parameters being a = 1293.2(2) pm, b = 1478.5(4) pm, c = 1507.2(3) pm, α = 98.86(3)°, β = 109.63(2)°, γ = 114.88(2)°, and Z = 2. Both compounds form arrays of eight‐membered rings (SnOPO)2 linked at the tin atoms to form chains of infinite length. The dimer 3 consists of a like ring, in which the tin atoms are bridged by methoxo groups. It crystallizes triclinic in space group with a = 946.4(1) pm, b = 963.7(1) pm, c = 1174.2(1) pm, α = 82.495(6)°, β = 66.451(6)°, γ = 74.922(6)°, and Z = 1 for the dimer. The Raman spectra of 2 and 3 are given and discussed. 相似文献
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Marina I. Naumova Natalia V. Kuratieva Dmitry Yu. Naumov Nina V. Podberezskaya 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(2):i14-i16
The structures of isomorphous monoclinic strontium and lead bis(dihydrogenphosphate), Sr(H2PO2)2 and Pb(H2PO2)2, and orthorhombic barium bis(dihydrogenphosphate), Ba(H2PO2)2, consist of layers of hypophosphite anions and metal cations exhibiting square antiprismatic coordination by O atoms. The Sr and Pb atoms are located on sites with point symmetry 2, and the Ba atoms are on sites with point symmetry 222. Within the layers, each anion bridges four metal cations. 相似文献