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891.
A new Cd(II) coordination polymer, namely, [Cd3(1,2,3-BTC)2(L)2]·2.25H2O (1, L = 2-(2-chloro-6-fluorophenyl)-1H-imidazo[4,5-A][1,10]phenanthroline and 1,2,3-BTC = 1,2,3-ben- zenetricarboxylate), has been synthesized under hydrothermal conditions. The compound was characterized by single-crystal X-ray diffraction. It crystallizes in triclinic, space group Pī with α = 11.650(2), b = 12.240(2), c = 19.760(4) A, α = 72.01(3), β = 77.11(3), γ = 83.48(3)°, V = 2609.4(9) A3, Z = 2, C56H31Cd3Cl2F2N8O14.25, Mr = 1489.99, Dc = 1.896 g/cm3, F(000) = 1466, μ(MoKa) = 1.401 mm^-1, R = 0.0401 and wR = 0.1104. Compound 1 shows a 1D chain structure, and the neigh- boring 1D chains of 1 are joined together by π···π interactions to result in a 2D supramolecular layer. In addition, the luminescent property of 1 has been studied in the solid state at room temperature.  相似文献   
892.
With the improvement of high-tech and emergence of crossing and new fields,lanthanide-transition(Ln–M) heterometallic coordination polymers have attracted much attention of many researchers,which exhibit novel structures and unique properties with potential applications in the nonlinear optical materials,fluorescent materials,superconducting materials,magnetic materials,catalysis,bio-simulation,adsorption and separation,and so on.It is thus necessary to summarize Ln–M heterometallic coordination polymers.According to the transition metal ions,those coordination polymers are divided into six parts to explore the current applications and future developments.  相似文献   
893.
A novel heterobimetaUic coordination polymer, {(NH4)2[Cd(H20)Fe(CN)6]}n 1, has been synthesized by using the slow diffusion method and structurally characterized by elemental analysis, 1R spectroscopy and single-crystal X-ray diffraction. The crystal crystallizes in the monoclinic system, space group P21/n, a = 7.4202(16), b = 14.939(3), c = 10.868(2) A and ,8 = 91.660(3)°. For 1, five CN groups of Fe(CN)6]4- are involved in bridging. The polymer displays a 3D open microporous framework with 5-connected uninodal (46.64) topology.  相似文献   
894.
文博  王晓丹  于颖慧  高金胜  侯广峰 《结构化学》2014,33(11):1603-1609
One new coordination polymer, [Ni(m-bix)(m-BDC)](1, m-bix = 1,3-bis(imidazol-1-ylmethyl)benzene, m-BDC = 1,3-benzenedicarboxylic acids), has been hydrothermally synthesized and structurally characterized by elemental analysis, IR, TGA and X-ray single-crystal diffraction. The green block crystal of complex 1(C22H18N4Ni O4) belongs to monoclinic system, space group P21/c with a = 10.0418(3), b = 23.8651(6), c = 8.7872(2) A, β = 112.333(3)o, V = 1947.88(9)A3, Z = 4, Dc = 1.572 g/cm3, Mr = 461.11, F(000) = 952, R = 0.0335 and w R = 0.0683 for 2827 observed reflections(I 2σ(I)). Complex 1 exhibits a novel 6-connected 3D sxd type topological framework. The magnetic characterization of complex 1 shows antiferromagnetic coupling exchange.  相似文献   
895.
洪东风  殷党跃  王俊儒  代江坤 《结构化学》2014,33(11):1636-1642
A new 3D heterometallic coordination polymer, namely [K2Pr2(C2O4)4·H2O]n(1), has been successfully synthesized under hydrothermal conditions. X-ray single-crystal diffraction determination reveals that 1 crystallizes in monoclinic system, space group P21/n with a = 12.060(4), b = 8.493(3), c = 15.776(5)(A), β = 93.235(3)°, V = 1613.4(9) 3, Z = 4, Mr = 730.12, Dc = 3.006 Mg/m3, μ = 6.581 mm-1, F(000) = 1368, the final R = 0.0283 and w R = 0.0866 for 2939 observed reflections with I 2σ(I). Complex 1 features an unusual 3D heterometallic coordination framework, in which oxalates exhibit three different coordination behaviours. Moreover, powder X-ray diffraction and thermal properties for 1 have also been investigated.  相似文献   
896.
江清柏  李胜良  汤旺  梁波 《化学通报》2014,77(9):893-893
聚合物锂离子电池作为储能装置在电子产品中具有广泛的应用前景。电极/聚合物电解质(E/P)界面相容性是影响聚合物锂离子电池电导率、安全性、机械性能的重要影响因素之一。研究E/P界面的电化学反应及形成机理,是解决相容性问题的关键。本文综述了近年来有关聚合物锂离子电池E/P界面相容性及相关研究技术的进展,并对聚合物锂离子电池界面相容性的相关研究进行了展望。  相似文献   
897.
Polymer network liquid crystal (PNLC) spatial light modulators are attractive for display and photonic applications because they can achieve submillisecond response time while keeping a large phase change. However, their on-state scattering caused by the grain boundary of LC multidomains hinders their applications. In this article, we review recent progress on the development of scattering-free PNLCs extending from short-wavelength infrared to visible region by reducing the domain sizes to ∼200 nm through low temperature curing process. To reduce operation voltage, both transmissive and reflective modes, LC material properties (birefringence and dielectric anisotropy), polymer composition and concentration, and pretilt angle effect are analyzed. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014 , 52, 183–192  相似文献   
898.
The deployment of high-energy-density lithium-metal batteries has been greatly impeded by Li dendrite growth and safety concerns originating from flammable liquid electrolytes. Herein, we report a stable quasi-solid-state Li metal battery with a deep eutectic solvent (DES)-based self-healing polymer (DSP) electrolyte. This electrolyte was fabricated in a facile manner by in situ copolymerization of 2-(3-(6-methyl-4-oxo-1,4-dihydropyrimidin-2-yl)ureido)ethyl methacrylate (UPyMA) and pentaerythritol tetraacrylate (PETEA) monomers in a DES-based electrolyte containing fluoroethylene carbonate (FEC) as an additive. The well-designed DSP electrolyte simultaneously possesses non-flammability, high ionic conductivity and electrochemical stability, and dendrite-free Li plating. When applied in Li metal batteries with a LiMn2O4 cathode, the DSP electrolyte effectively suppressed manganese dissolution from the cathode and enabled high-capacity and a long lifespan at room and elevated temperatures.  相似文献   
899.
Liquid vinyl monomers were converted into solid crystals via halogen bonding. They underwent solid-phase radical polymerizations through heating at 40 °C or ultraviolet photo-irradiation (365 nm). The X-ray crystallography analysis showed the high degree of monomer alignment in the crystals. The polymerizations of the solid monomer crystals yielded polymers with high molecular weights and relatively low dispersities because of the high degree of the monomer alignment in the crystal. As a unique application of this system, the crystalized monomers were assembled to pre-determined structures, followed by solid-phase polymerization, to obtain a two-layer polymer sheet and a three-dimensional house-shaped polymer material. The two-layer sheet contained a unique asymmetric pore structure and exhibited a solvent-responsive shape memory property and may find applications to asymmetric membranes and polymer actuators.  相似文献   
900.
A non-conjugated polymer acceptor PF1-TS4 was firstly synthesized by embedding a thioalkyl segment in the mainchain, which shows excellent photophysical properties on par with a fully conjugated polymer, with a low optical band gap of 1.58 eV and a high absorption coefficient >105 cm−1, a high LUMO level of −3.89 eV, and suitable crystallinity. Matched with the polymer donor PM6, the PF1-TS4-based all-PSC achieved a power conversion efficiency (PCE) of 8.63 %, which is ≈45 % higher than that of a device based on the small molecule acceptor counterpart IDIC16. Moreover, the PF1-TS4-based all-PSC has good thermal stability with ≈70 % of its initial PCE retained after being stored at 85 °C for 180 h, while the IDIC16-based device only retained ≈50 % of its initial PCE when stored at 85 °C for only 18 h. Our work provides a new strategy to develop efficient polymer acceptor materials by linkage of conjugated units with non-conjugated thioalkyl segments.  相似文献   
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