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草酸铽与水合环己烷六酸(H6LⅠ.H2O)(顺式椅式构型LⅠ:a,e,a,e,a,e)在水热条件下反应生成一种新颖的三维稀土配位聚合物[Tb4(LⅡ)(ox)3(H2O)8](LⅡ为反式椅式构型:e,e,e,e,e,e;ox为草酸根),通过元素分析和红外光谱对这个配位聚合物进行了表征。X射线单晶衍射分析表明该配合物属于三斜晶系,P1空间群,晶胞参数为:a=0.60203(4)nm,b=1.08278(8)nm,c=1.29446(9)nm,α=67.908 0(10)°,β=82.109 0(10)°,γ=83.887 0(10)°,V=0.773 07(9)nm3,Z=2。在这个配合物的形成中,顺式构型的H6LⅠ配体发生构型转变形成LⅡ配体,LⅡ配体采取μ8-桥连模式将Tb离子连接成一个具有孔洞的二维(Tb-LⅡ)配位层。由μ2-和μ4-桥连模式构成的一维(Tb-ox)链将二维(Tb-LⅡ)层连接成一个具有孔道的三维配位框架,ox配体和水分子通过配位作用和氢键作用填充在孔道中。 相似文献
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水热反应条件下,碳酸锰和碳酸钡分别与水合环己烷六酸(H6LⅠ·H2O)(顺式椅式构型LⅠ:a,e,a,e,a,e)反应生成2个三维的配位聚合物[Mg3(LⅡ)(H2O)6](1)和[Ba2(H2LⅡ)(μ2-H2O)2](2)(反式椅式构型LⅡ:e,e,e,e,e,e),通过元素分析和红外光谱对这2个配位聚合物进行了表征。X射线单晶衍射分析表明配合物1属于三方晶系,R3空间群,晶胞参数为:a=1.4393(2)nm,c=1.4597(4)nm,β=120.00°,V=2.6187(10)nm3,Z=18;配合物2结构属于单斜晶系,C2/c空间群,晶胞参数为:a=1.6764(2)nm,b=0.9095(1)nm,c=1.0001(1)nm,β=105.991(2)°,V=1.4659(2)nm3,Z=4。配合物1是由反式椅式构型LⅡ配体桥连形成的高对称性的三维配位网络。在配合物2中,顺式的H6LⅠ配体也发生构型转变并脱去部分羧基质子形成H2LⅡ配体,将Ba离子连接成一个具有一维孔道的三维有孔框架结构。在这2个配合物中,环己烷六酸配体均采取反式椅式LⅡ构型,证明了碱土金属离子Mg髤及Ba髤在水热条件下通过配位作用可以稳定环己烷六酸配体的这种反式椅式构型。 相似文献
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金属有机框架材料的研究进展 总被引:1,自引:0,他引:1
金属有机框架(metal-organic frameworks,MOFs)材料是一类由有机配体与金属中心经过自组装形成的具有可调节孔径的材料。与传统无机多孔材料相比,MOFs材料具有更大的比表面积,更高的孔隙率,结构及功能更加多样,因而已经被广泛应用于气体吸附与分离、传感器、药物缓释、催化反应等领域中。新兴材料的出现极大地促进了各个学科间的相互发展,本文综述了近年来MOFs材料的研究发展,包括MOFs材料自身的特点、国内外发展现状、应用领域以及复合MOFs材料的研究热点,并对今后的发展进行了展望。 相似文献
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通过水热法合成了三维(3D)网状金属有机框架物[Pr(NTA)(H2O)]n(NTA=nitrilotriacetic acid);利用元素分析、红外光谱分析、X射线单晶衍射等表征了产物的结构,利用热重分析和示差热重分析评价了其热稳定性,并测定了其磁性能.结果表明,目标配合物的Pr(Ⅲ)采取九配位模式(N1O8)形成三帽三角棱柱几何构型,配位聚合物通过O-C-O链组装成高度有序的3D结构.此外,合成的配合物具有较高的热稳定性,并因(O2C-C-C-CO2)2桥联而显示反铁磁性. 相似文献
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Lefebvre J Trudel S Hill RH Leznoff DB 《Chemistry (Weinheim an der Bergstrasse, Germany)》2008,14(24):7156-7167
The structure and properties of the K{Ni[Au(CN)(2)](3)} coordination polymer, prepared as a powder at room temperature and recrystallized hydrothermally, are reported. The structure of K{Ni[Au(CN)(2)](3)} contains triply-interpenetrated Prussian Blue type pseudo-cubic arrays assembled from the alternation of octahedral Ni(II) centers and [Au(CN)(2)](-) bridging units. SQUID magnetometry studies have shown that K{Ni[Au(CN)(2)](3)} displays typical paramagnetic behavior for isolated Ni(II) centers down to 1.8 K. However, the magnetic behavior of the samples prepared under hydrothermal conditions suggests a superparamagnetic signature superimposed onto a paramagnetic background. After investigating the samples by transmission electron microscopy, it was determined that, in addition to K{Ni[Au(CN)(2)](3)}, the high-temperature (125, 135, and 165 degrees C) aqueous reaction of Ni(NO(3))(2)6 H(2)O with KAu(CN)(2) also led to the formation of nanoparticles of NiO and Au as minor side products, and that these dominated the magnetic behavior. Nanoparticles of various sizes and shapes were observed, depending on the reaction conditions. Samples containing nanoparticles were found to be superparamagnetic, exhibiting blocking temperatures of approximately 17-22 K, consistent with the behavior expected for NiO nanoparticles. These results illustrate the extreme care that must be taken when examining the physical properties of apparently analytically pure materials prepared by hydrothermal methods. 相似文献
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在水热条件下以4-硝基邻苯二甲酸(4-H2nph)/2,2''-联吡啶-4,4''-二甲酸(H2bda)为主要配体,3-(2-吡啶基)吡唑(HL)/1,4-双(咪唑基-1-基)丁烷(bib)为辅助配体制备了2种新的金属有机配位聚合物[Cu4(4-nph)(L)6]n (1)和{[Cu2(bda)2(bib)2(H2O)4]·4H2O}n (2)。通过元素分析、红外光谱、热重X射线单晶衍射和X射线粉末衍射对它们进行了表征。结果表明,配合物1属于单斜晶系,C2/c空间群。晶胞参数:a=1.956 16(8) nm,b=1.290 68(8) nm,c=2.160 34(12) nm,β=97.073(2)°,V=5.412 9(5) nm3,Z=4。配合物2属于三斜晶系,P1空间群。晶胞参数:a=0.962 22(15) nm,b=1.102 90(17) nm,c=1.404 3(2) nm,α=72.752(4)°,β=79.271(4)°,γ=67.065 (3)°,V=1.306 6(4) nm3,Z=1。在配合物1中,羧基配体4-nph2-通过单齿模式桥联金属中心,形成一维结构。在配合物2中,柔性bib配体连接金属中心形成具有26元环的双核结构。此外,还用Gaussian16程序PBE0/LANL2DZ方法从配合物1的晶体结构中提取“分子片段”进行了量子化学计算。计算结果表明配位原子与铜(Ⅱ)离子之间存在着共价作用。 相似文献
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合成了4个杂金属杯[4]配位聚合物{[Cd(L)(tpa)]·3H2O}n(1),{[Zn2(L)2(tpa)2]·3H2O}n(2),{[Co(L)(oba)]·2DMA·0.5H2O}n(3)和{[Zn(L)(oba)]·DMA}n(4)(L=2-(1H-咪唑基-甲基)-6-(3-(1H-咪唑基-甲基)-5-叔丁基-2-羟基)苄基-4-叔丁基苯酚,H2tpa=对苯二甲酸,H2oba=4,4''-二苯醚二甲酸),并通过元素分析、热重、红外光谱、固态紫外、单晶X射线衍射和粉末X射线衍射对其进行了表征。单晶结构分析表明晶体1是单斜晶系,P21/n空间群,而晶体2,3和4均为三斜晶系,P1空间群。化合物1,2,3和4是由0维[M(N4O2C29H36)](M=Zn,Co,Cd)的杂金属杯[4]与配体对苯二甲酸和4,4''-二苯醚二甲酸形成的一维配位聚合物。 相似文献
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合成了4个杂金属杯[4]配位聚合物{[Cd(L)(tpa)]·3H2O}n(1),{[Zn2(L)2(tpa)2]·3H2O}n(2),{[Co(L)(oba)]·2DMA·0.5H2O}n(3)和{[Zn(L)(oba)]·DMA}n(4)(L=2-(1H-咪唑基-甲基)-6-(3-(1H-咪唑基-甲基)-5-叔丁基-2-羟基)苄基-4-叔丁基苯酚,H2tpa=对苯二甲酸,H2oba=4,4''-二苯醚二甲酸),并通过元素分析、热重、红外光谱、固态紫外、单晶X射线衍射和粉末X射线衍射对其进行了表征。单晶结构分析表明晶体1是单斜晶系,P21/n空间群,而晶体2,3和4均为三斜晶系,P1空间群。化合物1,2,3和4是由0维[M(N4O2C29H36)](M=Zn,Co,Cd)的杂金属杯[4]与配体对苯二甲酸和4,4''-二苯醚二甲酸形成的一维配位聚合物。 相似文献
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以4,4-二(4-羟乙基苯并咪唑基苯基)丙烷(L1),4,4-二(4-羟乙基咪唑基苯基)丙烷(L2)为原料,通过水热法得到2个二维结构的配位聚合物{[Cd(L1)(bdc)H2O]·2DMA}n(1),[Cd(L2)(bdc)H2O]n(2)(H2bdc=对苯二甲酸,DMA=N,N-二甲基乙酰胺),通过X-射线单晶洐射、热重以及红外光谱对其进行了表征。结果显示晶体1为单斜晶系,P2/c空间群。晶体2为单斜晶系,C2/c空间群。配合物2为2D→2D穿插结构。热重分析表明配合物1和2分别在343和325℃时分解。 相似文献
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以4,4-二(4-羟乙基苯并咪唑基苯基)丙烷(L1),4,4-二(4-羟乙基咪唑基苯基)丙烷(L2)为原料,通过水热法得到2个二维结构的配位聚合物{[Cd(L1)(bdc)H2O]·2DMA}n(1),[Cd(L2)(bdc)H2O]n(2)(H2bdc=对苯二甲酸,DMA=N,N-二甲基乙酰胺),通过X-射线单晶洐射、热重以及红外光谱对其进行了表征。结果显示晶体1为单斜晶系,P2/c空间群。晶体2为单斜晶系,C2/c空间群。配合物2为2D→2D穿插结构。热重分析表明配合物1和2分别在343和325℃时分解。 相似文献
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Schaate A Roy P Preusse T Lohmeier SJ Godt A Behrens P 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(34):9320-9325
We present the synthesis and characterization of porous interpenetrated zirconium-organic frameworks (PIZOFs), a new family of metal-organic frameworks obtained from ZrCl(4) and the rodlike dicarboxylic acids HO(2)C[PE-P(R(1),R(2))-EP]CO(2) H that consist of alternating phenylene (P) and ethynylene (E) units. The substituents R(1),R(2) were broadly varied (alkyl, O-alkyl, oligo(ethylene glycol)), including postsynthetically addressable substituents (amino, alkyne, furan). The PIZOF structure is highly tolerant towards the variation of R(1) and R(2). This together with the modular synthesis of the diacids offers a facile tuning of the chemical environment within the pores. The PIZOF structure was solved from single-crystal X-ray diffraction analysis. The PIZOFs are stable under ambient conditions. PIZOF-2, the PIZOF prepared from HO(2)C[PE-P(OMe,OMe)-EP]CO(2)H, served as a prototype to determine thermal stability and porosity. It is stable up to 325 °C in air as determined by using thermogravimetry and powder X-ray diffraction. Argon sorption isotherms on PIZOF-2 revealed a Brunauer-Emmett-Teller (BET) surface area of 1250 m(2) g(-1) and a total pore volume of 0.68 cm(3) g(-1). 相似文献
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Ibarra IA Lin X Yang S Blake AJ Walker GS Barnett SA Allan DR Champness NR Hubberstey P Schröder M 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(46):13671-13679
Two new three-dimensional Sc(III) metal-organic frameworks {[Sc(3)O(L(1))(3)(H(2)O)(3)]·Cl(0.5)(OH)(0.5)(DMF)(4)(H(2)O)(3)}(∞) (1) (H(2)L(1)=1,4-benzene-dicarboxylic acid) and {[Sc(3)O(L(2))(2)(H(2)O)(3)](OH)(H(2)O)(5)(DMF)}(∞) (2) (H(3)L(2)=1,3,5-tris(4-carboxyphenyl)benzene) have been synthesised and characterised. The structures of both 1 and 2 incorporate the trinuclear trigonal planar [Sc(3)(O)(O(2)CR)(6)] building block featuring three Sc(III) centres joined by a central μ(3)-O(2-) donor. Each Sc(III) centre is further bound by four oxygen donors from four different bridging carboxylate anions, and a molecule of water located trans to the μ(3)-O(2-) donor completes the six coordination at the metal centre. Frameworks 1 and 2 show high thermal stability with retention of crystallinity up to 350 °C. The desolvated materials 1a and 2a, in which the solvent has been removed from the pores but with water or hydroxide remaining coordinated to Sc(III), show BET surface areas based upon N(2) uptake of 634 and 1233 m(2) g(-1), respectively, and pore volumes calculated from the maximum N(2) adsorption of 0.25 cm(3) g(-1) and 0.62 cm(3) g(-1), respectively. At 20 bar and 78 K, the H(2) isotherms for desolvated 1a and 2a confirm 2.48 and 1.99 wt% total H(2) uptake, respectively. The isosteric heats of adsorption were estimated to be 5.25 and 2.59 kJ mol(-1) at zero surface coverage for 1a and 2a, respectively. Treatment of 2 with acetone followed by thermal desolvation in vacuo generated free metal coordination sites in a new material 2b. Framework 2b shows an enhanced BET surface area of 1511 m(2) g(-1) and a pore volume of 0.76 cm(3) g(-1), with improved H(2) uptake capacity and a higher heat of H(2) adsorption. At 20 bar, H(2) capacity increases from 1.99 wt% in 2a to 2.64 wt% for 2b, and the H(2) adsorption enthalpy rises markedly from 2.59 to 6.90 kJ mol(-1). 相似文献
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Zacher D Schmid R Wöll C Fischer RA 《Angewandte Chemie (International ed. in English)》2011,50(1):176-199
Metal-organic frameworks (MOFs) are a fascinating class of novel inorganic-organic hybrid materials. They are essentially based on classic coordination chemistry and hold much promise for unique applications ranging from gas storage and separation to chemical sensing, catalysis, and drug release. The evolution of the full innovative potential of MOFs, in particular for nanotechnology and device integration, however requires a fundamental understanding of the formation process of MOFs. Also necessary is the ability to control the growth of thin MOF films and the positioning of size- and shape-selected crystals as well as MOF heterostructures on a given surface in a well-defined and oriented fashion. MOFs are solid-state materials typically formed by solvothermal reactions and their crystallization from the liquid phase involves the surface chemistry of their building blocks. This Review brings together various key aspects of the surface chemistry of MOFs. 相似文献
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在溶剂热条件下,基于芳香四羧酸合成了2种新颖的配位聚合物:{[Zn2(tptc)(1,4-bimb)2]·H2O}n(1)和{[Ni(tptc)0.5(1,2-bimb)(H2O)]·H2O}n(2),其中,tptc为对-三联苯-3,3″,5,5″-四羧酸,1,4-bimb为1,4-二(咪唑-1-亚甲基)苯,1,2-bimb为1,2-二(咪唑-1-亚甲基)苯。结构分析表明,1为三维结构,拓扑符号为(86);2为二维层状网络,通过氢键相互作用进一步扩展为三维超分子结构。此外,我们还研究了1对阳离子、阴离子的荧光感应以及2的磁性质。 相似文献
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Saalfrank RW Maid H Scheurer A 《Angewandte Chemie (International ed. in English)》2008,47(46):8794-8824
Supramolecular coordination compounds bear exceptional advantages over their organic counterparts. They are available in one-pot reactions and in high yields and display physical properties that are generally inaccessible with organic species. Moreover, their weak, reversible, noncovalent bonding interactions facilitate error checking and self-correction. This Review emphasizes the achievements in supramolecular coordination chemistry initiated by serendipity and their materialization based on rational design. The recognition of similarities in the synthesis of different supramolecular assemblies allows prediction of potential results in related cases. Supramolecular synthesis obeys guidelines comparable to the "lead sheet" used by small jazz ensembles for improvisation and therefore more often leads to unpredicted results. The combination of detailed symmetry considerations with the basic rules of coordination chemistry has only recently allowed for the design of rational strategies for the construction of a variety of nanosized systems with specified size and shape. 相似文献
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通过水热法合成了两种锌配位聚合物{[Zn(ic)(bip)]·2H2O}n(1)和[Zn(ic)(bpe)]n(2)(H2ic=衣康酸,bip=3,5-二(1-咪唑基)吡啶,bpe=1,2-二(4-吡啶基)乙烯),并通过X射线单晶衍射和元素分析对其结构进行了表征。配合物1和2均为含有一维金属-羧酸链的二维(4,4)格子层结构。此外,对它们的热重、粉末X射线衍射和固体荧光性能进行了考察。与配体bip相比,1的发射光谱发生了明显的蓝移(78 nm),可能归因于配体到金属的电荷转移;2显示与游离的bpe配体相似的荧光性质,轻微的红移可能是因为与金属离子之间的配位作用导致的。 相似文献
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通过水热法合成了两种锌配位聚合物{[Zn(ic)(bip)]·2H2O}n (1)和[Zn(ic)(bpe)]n (2)(H2ic=衣康酸,bip=3,5-二(1-咪唑基)吡啶,bpe=1,2-二(4-吡啶基)乙烯),并通过X射线单晶衍射和元素分析对其结构进行了表征.配合物1和2均为含有一维金属-羧酸链的二维(4,4)格子层结构.此外,对它们的热重、粉末X射线衍射和固体荧光性能进行了考察.与配体bip相比,1的发射光谱发生了明显的蓝移(~78 nm),可能归因于配体到金属的电荷转移;2显示与游离的bpe配体相似的荧光性质,轻微的红移可能是因为与金属离子之间的配位作用导致的. 相似文献