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1.
Broken switch : Guest‐accessible metal sites are generated on the pore surface of a porous coordination polymer (see figure) through the complementary coordination‐bond rearrangement in a single‐crystal‐to‐single‐crystal fashion, which is triggered by the removal of coordinated water.

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2.
Summary: A novel coordination polymer[{Cu(en)2}(V10O28)]n · 2n[Cu(en)2(H2O)] · 2n(H3BO3) · 2n(H2O) was obtained by hydrothermal reaction. The compound crystallizes in the monoclinic crystal system, in the C2/c space group, with a = 26.490 (3) Å; b = 11.6558 (11) Å; c = 19.8426 (19) Å; β = 124.011 (1)°; V = 5078.6(8) Å3. The solid structure is formed by polymeric chains, [Cu(en)2(H2O)]2+ cations, and boric acid and water solvate molecules, stabilized through a multiple hydrogen bond network.  相似文献   

3.
The separation of 1,3‐butadiene from C4 hydrocarbon mixtures is imperative for the production of synthetic rubbers, and there is a need for a more economical separation method, such as a pressure swing adsorption process. With regard to adsorbents that enable C4 gas separation, [Zn(NO2ip)(dpe)]n (SD‐65; NO2ip=5‐nitroisophthalate, dpe=1,2‐di(4‐pyridyl)ethylene) is a promising porous material because of its structural flexibility and restricted voids, which provide unique guest‐responsive accommodation. The 1,3‐butadiene‐selective sorption profile of SD‐65 was elucidated by adsorption isotherms, in situ PXRD, and SSNMR studies and was further investigated by multigas separation and adsorption–desorption‐cycle experiments for its application to separation technology.  相似文献   

4.
Single‐ligand‐based electronically conductive porous coordination polymers/metal–organic frameworks (EC‐PCPs/MOFs) fail to meet the requirements of numerous electronic applications owing to their limited tunability in terms of both conductivity and topology. In this study, a new 2D π‐conjugated EC‐MOF containing copper units with mixed trigonal ligands was developed: Cu3(HHTP)(THQ) (HHTP=2,3,6,7,10,11‐hexahydrotriphenylene, THQ=tetrahydroxy‐1,4‐quinone). The modulated conductivity (σ≈2.53×10?5 S cm?1 with an activation energy of 0.30 eV) and high porosity (ca. 441.2 m2 g?1) of the Cu3(HHTP)(THQ) semiconductive nanowires provided an appropriate resistance baseline and highly accessible areas for the development of an excellent chemiresistive gas sensor.  相似文献   

5.
The glassy state of a two‐dimensional (2D) Cd2+ coordination polymer crystal was prepared by a solvent‐free mechanical milling process. The glassy state retains the 2D structure of the crystalline material, albeit with significant distortion, as characterized by synchrotron X‐ray analyses and solid‐state multinuclear NMR spectroscopy. It transforms to its original crystal structure upon heating. Thus, reversible crystal‐to‐glass transformation is possible using our new processes. The glass state displays superior properties compared to the crystalline state; specifically, it shows anhydrous proton conductivity and a dielectric constant two orders of magnitude greater than the crystalline material. It also shows material flexibility and transparency.  相似文献   

6.
Luminescent copper(I)-based compounds have recently attracted much attention since they can reach very high emission quantum yields. Interestingly, Cu(I) clusters can also be emissive, and the extension from small molecules to larger architecture could represent the first step towards novel materials that could be obtained by programming the units to undergo self-assembly. However, for Cu(I) compounds the formation of supramolecular systems is challenging due to the coordinative diversity of copper centers. This works shows that this diversity can be exploited in the construction of responsive systems. In detail, the changes in the emissive profile of different aggregates formed in water by phosphine-thioether copper(I) derivatives were followed. Our results demonstrate that the self-assembly and disassembly of Cu(I)-based coordination polymeric nanoparticles (CPNs) is sensitive to solvent composition. The solvent-induced changes are related to modifications in the coordination sphere of copper at the molecular level, which alters not only the emission profile but also the morphology of the aggregates. Our findings are expected to inspire the construction of smart supramolecular systems based on dynamic coordinative metal centers.  相似文献   

7.
The compound (C4C1py)[Cu(SCN)2], (C4C1py=1‐Butyl‐4‐methyl‐pyridinium), which can be obtained from CuSCN and the ionic liquid (C4C1py)(SCN), turns out to be a new organic–inorganic hybrid material as it qualifies both, as a coordination polymer and an ionic liquid. It features linked [Cu(SCN)2]? units, in which the thiocyanates bridge the copper ions in a μ1,3‐fashion. The resulting one‐dimensional chains run along the a axis, separated by the C4C1py counterions. Powder X‐ray diffraction not only confirms the single‐crystal X‐ray structure solution but proves the reformation of the coordination polymer from an isotropic melt. However, the materials shows a complex thermal behavior often encountered for ionic liquids such as a strong tendency to form a supercooled melt. At a relatively high cooling rate, glass formation is observed. When heating this melt in differential scanning calorimetry (DSC) and temperature‐dependent polarizing optical microscopy (POM), investigations reveal the existence of a less thermodynamically stable crystalline polymorph. Raman measurements conducted at 10 and 100 °C point towards the formation of polyanionic chain fragments in the melt. Solid‐state UV/Vis spectroscopy shows a broad absorption band around 18 870 cm?1 (530 nm) and another strong one below 20 000 cm?1 (<500 nm). The latter is attributed to the d(CuI)→π*(SCN)‐MLCT (metal‐to‐ligand charge transfer) transition within the coordination polymer yielding an energy gap of 2.4 eV. At room temperature and upon irradiation with UV light, the material shows a weak fluorescence band at 15 870 cm?1 (630 nm) with a quantum efficiency of 0.90(2) % and a lifetime of 131(2) ns. Upon lowering the temperature, the luminescence intensity strongly increases. Simultaneously, the band around 450 nm in the excitation spectrum decreases.  相似文献   

8.
Optimal control of gas adsorption properties in metal–organic frameworks (MOFs) or porous coordination polymers (PCPs) remains a great challenge in the field of materials science. An efficient strategy to capture electron-acceptor-type gas molecules such as nitrogen monooxide (NO) is to use host–guest interactions by utilizing electron-donor-type MOFs/PCPs as host frameworks. Herein, we focus on a highly electron-donating chain compound by using the paddlewheel-type [Ru2II,II] complex [Ru2(2,4,5-Me3PhCO2)4] (2,4,5-Me3PhCO2=2,4,5-trimethylbenzoate) with the phenazine (phz) linker: [Ru2(2,4,5-Me3PhCO2)4(phz)] ( 1 ). Compound 1 exhibited a specific gated adsorption for NO under gas pressures greater than 60 kPa at 121 K, which finally resulted in approximately seven molar equivalents being taken up at 100 kPa followed by four molar equivalents remaining under vacuum at 121 K; its Rh isomorph ( 2 ) with weaker donation ability was inactive for NO. When the sample of 1 ⊃4 NO was heated to room temperature, the compound underwent a crystal-to-crystal phase transition to give [Ru2(2,4,5-Me3PhCO2)4(NO)2](phz) ( 1 -NO), involving a post-synthetic nitrosylation on the [Ru2] unit, accompanied by an eventful site-exchange with phz. This drastic event, which is dependent on the NO pressure, temperature, and time, was coherently monitored by using several different in situ techniques, revealing that the stabilization of NO molecules in nanosized pores dynamically and stepwisely occurred with the support of strong electronic/magnetic host–guest interactions.  相似文献   

9.
A metal-organic coordination polymer {[Zn(Pht)(4,4′-bipy)(H2O)2]·2H2O}n (Pht = phthalate, 4,4′-bipy = 4,4′-bipyridine) 1 has been hydrothermally synthesized and characterized by elemental analysis, IR, TG, fluorescence spectrum and single-crystal X-ray diffraction. Yellow crystals crystallize in the monoclinic system, space group P2/n, a = 7.6346(14), b = 11.316(2), c = 10.8133(19) (A), β = 92.444(3)o, V = 933.3(3)(A)3, C18H20N2O8Zn, Mr = 457.73, Dc = 1.629 g/cm3, F(000) = 472, Z = 2, μ(MoKα) = 1.367 mm-1, the final R = 0.0323 and wR = 0.0821 for 1859 observed reflections (I > 2σ(I)). The structure of 1 exhibits a two-dimensional bilayer framework formed by hydrogen bonding interactions. Furthermore, 1 shows yellow photoluminescent pro- perty at room temperature.  相似文献   

10.
Making connections : A hydroxy‐centered trinuclear nickel cluster has been employed to construct a highly connected, highly symmetric framework with a uninodal nine‐connected topology. An array of triakis tetrahedra leads to a biporous intersecting‐channel system (see picture).

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11.
12.
1 INTRODUCTION Inorganic coordination polymers or solid-state po- lymers have received considerable attention in the past few years due to their possible applications as new materials in catalysis, adsorption, ion exchange, separation, magnetic devices, etc.[1] Metal coordina- tion polymers containing dicarboxylate ions as the organic spacer have been the subject of particular interest due to their fascinating architectures and ad- vantageous properties, such as bulk magnetic beha- vior, h…  相似文献   

13.
IntroductionSelf assembledinfinitecoordinationpolymersandsupramoleculeswithspecificnetworktopologieshaveattractedconsiderableattentionduetotheirpotentialap plicationsasfunctionalmaterialsaswellasfascinatingmolecularandcrystalstructures .Whilethevastmaj…  相似文献   

14.
朱志博  路新卫 《结构化学》2010,29(3):465-470
A new 1D coordination polymer,{[Mn2(4',4-hbc)4(4',4-Hhbc)2(H2O)]·H2O}n(4',4-Hhbc=4'-hydroxyl-biphenyl-4-carboxylic acid),has been hydrothermally synthesized and struc-turally characterized by elemental analysis,IR spectroscopy and single-crystal X-ray diffraction.The crystal belongs to the monoclinic system,space group C2/c with a=52.421(10),b=7.5388(15),c=16.478(3),β=106.12(3)°,V=6256(2)3,Z=4,C78H62Mn2O21,Mr=1445.16,Dc=1.534g/cm3,μ(MoKα)=0.490mm-1,F(000)=2992,R=0.0764 and wR=0.2006 for 2984 observed reflections with I2σ(I).X-ray diffraction analyses reveal that the title compound is a one-dimensional infinite chain,in which the MnⅡ atom adopts a distorted octahedral geometry coordinated by four 4',4-hbc ligands,one 4',4-Hhbc ligand and one water molecule.Furthermore,the luminescent property of title compound was investigated.  相似文献   

15.
魏梅林  蒋凯  孙瑞平 《结构化学》2009,28(2):157-162
A porous coordination polymer, {[Ce(dpdo)4(H2O)3](PMo_12O_40)(dpdo)0.5(H2O)4}n 1 (dpdo = 4,4'-bipyridine-N,N'-dioxide), templated by double-Keggin-type polyanions was synthesized and structurally characterized. The crystal structure was determined by single-crystal X- ray diffraction. The crystal is of triclinic, space group P1 with a = 13.368(4), b = 16.503(4), c = 18.506(5)А, α = 88.831(5), β= 82.095(5), γ = 83.578(5)°,V= 4018.6(18)А^3, Z=2, C45H50N9O56CeMo12P, Mr = 2935.31, Dc = 2.426 g/m^3, μ= 2.491 mm^-1, F(000) = 2816, the final R=0.0603 and wR = 0.1611 for 11977 observed reflections with I 〉 2σ(I). Compound 1 exhibits a 3D non-interwoven framework with large cavities housing centrosymmetrically related shoulder-by-shoulder double-Keggin anions as guests.  相似文献   

16.
The complexes [MCl2(TzH)4] (M=Mn ( 1 ), Fe ( 2 ); TzH=1,2,4‐1H‐triazole) and [ZnCl2(TzH)2] ( 3 ) have been obtained by mechanochemical reactions of the corresponding divalent metal chloride and 1,2,4‐1H‐triazole. They were successfully used as precursors for the formation of coordination polymers either by a microwave‐assisted reaction or by thermal conversion. For manganese, the conversion directly yielded [MnCl2TzH] ( 4 ), whereas for the iron‐containing precursor, [FeCl2TzH] ( 6 ), was formed via the intermediate coordination polymer [FeCl(TzH)2]Cl ( 5 ). For cobalt, the isotypic polymer [CoCl(TzH)2]Cl ( 7 ) was obtained, but exclusively by a microwave‐induced reaction directly from CoCl2. The crystal structures were resolved from single crystals and powders. The dielectric properties were determined and revealed large differences in permittivity between the precursor complexes and the rigid chain‐like coordination polymers. Whereas the monomeric complexes exhibit very different dielectric behaviour, depending on the transition metal, from “low‐k” to “high‐k” with the permittivity ranging from 4.3 to >100 for frequencies of up to 1000 Hz, the coordination polymers and complexes with strong intermolecular interactions are all close to “low‐k” materials with very low dielectric constants up to 50 °C. Therefore, the conversion procedures can be used to deliberately influence the dielectric properties from complex to polymer and for different 3d transition‐metal ions.  相似文献   

17.
配位聚合物以其新颖的拓扑结构和独特的电学、磁学、光学和催化等物理和化学性质引起人们极大的研究热情。配位聚合物的结构取决于很多因素,例如中心原子的选择、配体的选择、阴离子的变化等。在这些因素中选用合适的配体无疑是控制配位聚合物拓扑结构的关键因素之一[1 ̄10]。含有三氮唑、咪唑等含N基团的有机桥联配体由于其配位能力强、配位原子数目多、易与过渡金属离子形成具有特殊结构的配合物等特点引起人们极大兴趣,成为近年来配位化学的研究热点之一。在含N配体的研究中,双齿桥联三唑类柔性配体如1,2-二(1H-1,2,4-三唑)乙烷和1,4-…  相似文献   

18.
陈新  张明星  黄坤林 《结构化学》2012,31(11):1601-1607
A new metal-organic coordination polymer [Pb(mfpdc)(CH3OH)]n (1, mfpdc=2,6-dimethyl-4-(2-furanyl) pyridine-3,5-dicarboxylate) was synthesized and characterized by single-crystal X-ray analyses. The crystal is orthorhombic, space group Pbca, a=15.6297(18), b=9.4803(11), c=18.598(2), V=2755.8(6)3 , Z=8, Mr=498.44, Dc=2.403 Mg/m3 , F(000)=1872, the final R=0.0275 and wR=0.0726 (I>2 (I)). There are interesting polynuclear zigzag (PbO5 ) n chains in the structure of 1, and there have interesting axially chiral S-and R-unit Pb4L units constructed from prochiral organic ligands through C-H···O bonding. The (R/S)-Pb4L units by sharing Pb centers generate a 2-D coordination network, in which there exist rare π65 ···Pb(3.2610 ) interactions. The solid-state photoluminescent emission of compound 1 appears at 487 nm.  相似文献   

19.
一维链状铜(Ⅱ)配合物的合成及晶体结构表征   总被引:1,自引:0,他引:1  
The 1D-chain polymer of [Cu(Ⅱ)3L3(H2O)]n, (H2L=3-(3,5-dichloro-2-hydroxybenzylid-eneamino)propanoic acid) has been synthesized by reaction of 3,5-dichlorosalicylaldehyde, β-alamine and copper nitrate in ethanol solution. The crystal structure was determined by X-ray diffraction method. The crystal structure belongs to mono-clinic system with space group C2/c and cell parameters: a=3.853 7(3) nm, b=0.777 38(18) nm, c=2.656 36(2) nm, β=116.924(2)° and V=7.095 4(17) nm3, Mr=998.85, Z=8, Dc=1.870 g·cm-3 and F(000)=3 992. The two Cu(Ⅱ) atoms are coordinated with four atoms from Schiff base, and another one is coordinated with five atoms. The square bridging links three metal centers through a novel μ-4,4,5 coordination model, which is further assembled into 1D chain coordination polymer. The 1D chain is further constructed a 3D network by strong O-H…O and C-H…O hydrogen bonds. The coordination polymer presents a good thermal stable property through the thermal analysis. CCDC: 679005.  相似文献   

20.
徐中轩  石明凤 《无机化学学报》2019,35(12):2346-2354
利用水热合成条件,在辅助配体帮助下,乳酸衍生物与Zn2+反应合成出了2对单一手性的配位聚合物,即{[Zn((R)-CBA)(1,3-DIMB)]·H2O}n1-D)、{[Zn((S)-CBA)(1,3-DIMB)]·H2O}n1-L)、[Zn2((R)-CBA)2(1,4-BMIP)]n2-D)和[Zn2((S)-CBA)2(1,4-BMIP)2]n2-L)。结构分析揭示上述所有配合物都包含由CBA2-配体与Zn(Ⅱ)离子构建而成的螺旋链。此外,刚性的辅助配体1,3-DIMB和1,4-BMIP在结构多样性中发挥了重要作用。测试了配合物的热稳定性、固态圆二色谱、荧光性质等。研究结果表明半刚性乳酸配体可以有效地合成螺旋结构的单一手性配位聚合物。  相似文献   

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