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A new nonlinear optical crystal [Ca2B5O9]·[H(OH)2] (1) has been synthesized under hydrothermal condition. Compound 1 crystallizes in the monoclinic space group C2 with lattice constants a = 10.111(2) Å, b = 7.754(11) Å, c = 6.198(14) Å, β = 127.04(3)° and Z = 2. The fundamental building block (FBB) of 1 is a [B5O12] unit with two BO3 triangles and three BO4 tetrahedra. 1 was characterized by single-crystal X-ray diffraction, IR and UV–Vis spectroscopy, thermogravimetric analysis (TGA), powder X-ray diffraction (PXRD) respectively. Also, powder second harmonic generation (SHG) measurements indicate that 1 is phase matchable and displays a SHG response of about 3.5 times that of KDP (KH2PO4).  相似文献   

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The high-pressure behavior of kernite [ideally Na2B4O6(OH)2·3H2O, a ~ 7.02 Å, b ~ 9.16 Å, c ~ 15.68 Å, β = 108.9°, Sp Gr P21/c, at ambient conditions], an important B-bearing raw material (with B2O3 ≈ 51 wt%) and a potential B-rich aggregate in radiation shielding materials, has been studied by single-crystal synchrotron X-ray diffraction up to 14.6 GPa. Kernite undergoes an iso-symmetric phase transition at 1.6-2.0 GPa (to kernite-II). Between 6.6-7.5 GPa, kernite undergoes a second phase transition, possibly iso-symmetric in character (to kernite-III). The crystal structure of kernite-II was solved and refined. The isothermal bulk modulus (KV0 = β-1P0,T0, where βP0,T0 is the volume compressibility coefficient) of the ambient-pressure polymorph of kernite was found to be KV0 = 29(1) GPa and a marked anisotropic compressional pattern, with K(a)0: K(b)0: K(c)0~1:3:1.5., was observed. In kernite-II, the KV0 increases to 43.3(9) GPa and the anisotropic compressional pattern increases pronouncedly. The mechanisms, at the atomic scale, which govern the structure deformation, have been described.  相似文献   

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X-ray crystallography reveals four isostructural lanthanide polymeric solids, [Ln2(atp)3(H2O)2]·dmf·4H2O (atp = 2-aminoterephthalate; dmf = N,N′-dimethylformamide; Ln = La (1), Ce (2), Pr (3) and Nd (4), respectively) that are obtained from the solvothermal synthesis which are crystallized in an interesting 3D polymeric framework with a (4,4,6)-linked {42·84}{44·62}2{48·66·8}2 fsy net topology. Upon excitation at 350 nm, they all show the solid state ligand-centered luminescences but both 2 and 3 also exhibit the weak lanthanide-based characteristic emissions in the visible region at room temperature. The cyclic voltammetric investigation indicates that 2 exhibits appreciable electrochemical activity for formaldehyde.  相似文献   

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The title compound, s-fac-[Co(dien)2][B7O9(OH)6]·9H2O (1) (dien = HN(CH2CH2NH2)2), has been prepared as a crystalline solid in moderate yield (35%) from the reaction of B(OH)3 with [Co(dien)2][OH]3 in aqueous solution (10:1 ratio). The structure contains a novel polyborate anion [B7O9(OH)6]3  which is structurally based on the known ‘ribbon’ isomer of [B7O9(OH)5]2 , with an additional [OH] group coordinated to a B atom in one of the outer boroxole rings. Compound 1 is formed by a self-assembly process in which the cation and anion mutually template themselves from equilibrium mixtures under reaction conditions. The [B7O9(OH)6]3  anions are H-bonded to each other in layers with ‘cavities’ suitable for the [Co(dien]2]3 + complex. Three [B7O9(OH)6]3  anions are in the secondary coordination sphere (via H-bonds) of each cation, with each anion H-bonded to three cations.  相似文献   

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Two novel copper(II) complexes, namely [Cu(phen)(L)2]·6H2O (1) and [Cu(phen)3]·(ClO4)2 (2) have been synthesized under mild condition (HL = 5-methyl-1H-pyrazole-3-carboxylic acid, phen = 1,10-phenanthroline). We report the structural evidence of discrete water decamer conformation in the solid state. These units are found to act as supramolecular glue in the aggregation of mononuclear copper(II) complex to give a three-dimensional network through hydrogen-bonding. The preliminary investigation on the thermal behavior and the anion exchange property of the complexes are presented.  相似文献   

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在温和条件下合成了一种有机胺硼酸盐[C4H12N]·[B5O6(OH)4],通过单晶衍射的手段解析其晶体结构.在不同温度下对该物质进行加热,观察其红外光谱的变化判断其内部的结构是否能够保持稳定,并通过热重分析进行补充说明.紫外发光光谱的测试表明,使用368 nm的激发光照射样品,可以得到430 nm,470 nm的发射光谱.在不同温度下加热后,该物质的发光特性发生明显的变化.这种变温的改性实验证实有机胺硼酸盐是一种可能的白光LED上的蓝光材料.  相似文献   

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Continuing our work on the synthesis of MoO2L2 and MoO3LALB that show excellent anti-cancer activities in vitro, the MoL3 have been synthesized by the solvothermal reaction of Na2MoO4 with catechols and 1,2-DPA in the mixed solvent of MeCN/MeOH. X-ray diffraction revealed that Mo in chiral octahedral geometry coordinate with three catechol ligands formed three five-membered rings, and the [Mo(C6H4O2)3] are linked by hydrogen bonds Mo(OC6H4)O…H–N(C4H8O)N–H…O(C6H4O)Mo through the by-product (C4H8N2O) that are formed by one 1,2-DPA with one CO2 on the catalysis of Mo-complex. Also, we have disassembled bulk crystal into nano-aggregates, and under TEM mono-lamella morphology of nanostructures was observed, which agrees well with the previous conclusion that the morphologies of the nano-aggregates are associated with the quantum motifs in their crystal lattices. [Mo(C6H4O2)3] have also been characterized by UV–vis spectra, cyclic voltammogram and thermogravimetric analysis.  相似文献   

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《分离科学与技术》2012,47(2):232-240
Prussian blue analogue of porous Mn3[Co(CN)6]2 · nH2O nanospheres with a large surface area were prepared by simple mixing K3[Co(CN)6]2 and manganous nitrate solution at room temperature. The morphology and structure of the prepared products were characterized by XRD, FE-SEM, TEM, and BET. The results indicated that the product was composed of nanospheres with the diameter of ~250 nm, which was of porous structure with the pore diameter in the 2.5–4 nm range. The adsorption behavior of Cu(II) ions from aqueous solution onto porous nanospheres was investigated as a function of parameters, such as the equilibrium time, the pH, the initial concentration, and the temperature. A maximum adsorption capacity of 140.85 mg g?1 of Cu(II) was achieved. Due to the simple synthetic method and its high adsorption capacity, the porous nanospheres had the potential to be utilized as an effective adsorbent for Cu(II) removal.  相似文献   

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Two inorganic–organic hybrid supramolecular compounds based on polyoxometalates formulated as (C4H8NH2)4[Mo8O26] (1) and (NH4)Na2[AsIIIMo6O21(O2CCH2NH3)3]·8H2O (2) have been synthesized by conventional solution method and characterized by infrared, UV–Vis and single-crystal X-ray diffraction analyses. Thermal analysis was performed to study their thermal stability. The atomic arrangement in compound (1) can be described as inorganic layers built by [Mo8O26]4?, pyrrolidinium cations are embedded into layers. The fascinating structural feature of compound (2) is that the glycine molecules are bounded to two edge-sharing Mo centers via their carboxylate functionality leading to functionalized heteropolymolybdate [AsIIIMo6O21(O2CCH2NH3)3]3?, extensive net hydrogen bonds between cations and anions contribute to the crystal packing. The electrochemical behavior of compound (2) has been studied.  相似文献   

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《广州化工》2021,49(16)
以FeCl_3·6H_2O和Ni_3[Ge_2O_5]·(OH)_4为原料,通过水浴辅助液相沉积法一步制备了α-Fe_2O_3/Ni_3[Ge_2O_5]·(OH)_4纳米复合材料,利用X射线衍射(XRD)、场发射扫描电子显微镜(FE-SEM)、高分辨透射电镜(HTEM)、紫外-可见吸收光谱(UV-Vis)等表征手段对样品的物相组成、形貌、尺寸及光吸收特性等进行了分析表征。在自然光、室温条件下,以罗丹明B溶液的催化脱色降解为模型反应,探究了不同α-Fe_2O_3负载量对纳米α-Fe_2O_3/Ni_3[Ge_2O_5](OH)_4复合材料降解罗丹明B性能的影响规律。结果表明,利用该法可以得到纳米级的、相互之间紧密复合的α-Fe_2O_3/Ni_3[Ge_2O_5](OH)_4复合材料;当复合材料中α-Fe_2O_3与Ni_3[Ge_2O_5]·(OH)_4的质量比为1:10时得到的纳米复合材料在氙灯光照条件下具有最佳的催化性能,180 min脱色率可达89.35%。是相同条件下α-Fe_2O_3脱色率的11.6倍。  相似文献   

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Topics in Catalysis - Alpha phase bismuth oxide (α-Bi2O3) microparticles were prepared through the annealing at 600 °C of basic bismuth nitrate [Bi6O6(OH)2(NO3)4·2H2O]...  相似文献   

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The decavanadate with a novel glycine–glycinato complex of copper (II) in the cationic part, (NH4)2[Cu2(H2O)4(NH3CH2COO)2(NH2CH2COO)2]H2V10O28·6H2O (1), has been prepared and characterized by elemental analysis, infrared and EPR spectroscopies. The triplet X band EPR spectrum of powdered sample evidenced magnetic interaction between the Cu(II) atoms in the dimeric unit which is probably realized through the bridging water molecules in this part of the complex. A single crystal X-ray diffraction study revealed that the structure of 1 contains cationic copper complex with a rare Cu(H2O)2Cu double bridge. In this cation, a simultaneous bidentate N, O– and monodentate O– coordination of glycine to the same central atom was observed for the first time.  相似文献   

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用2-羧基吡啶和六水合氯化锌反应制备了一种新的三维氢键超分子配合物,经X-射线衍射分析确定了单晶结构。该晶体属单斜晶系,P2(1)/n空间群,晶胞参数为:a=9.836(2),b=5.2256(10),c=14.611(3),Mr=381.64,β=90.01(3)°,V=751.0(3)3,Z=2,Dc=1.688Mg.m-3,F(000)=392,μ=1.680mm-1,R=0.0258,wR=0.0612。共收集2159个衍射数据,其中1273个为独立衍射点(Rint=0.0332),可观测点数1139个(I>2σ(I))。结果表明,在组成该超分子体系的基本结构单元[Zn(C6H4O2N)2.(H2O)4]中,Zn(Ⅱ)离子形成六配位的畸变的八面体构型,配合物单元之间通过氢键OH…O相互连接,形成了无限延伸的具有网状结构的三维超分子体系。  相似文献   

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A novel and large heteropolyanion [(BiW9O33)3Bi6(OH)3(H2O)3V4O10]12− has been synthesized by reaction of sodium metavanadate with Na9[BiW9O33]·16H2O in acetate buffer solutions (at pH 4.8). The present anion has a trilobal structure in which three α-B {BiW9O33} units are connected to each other by an unique core [Bi6(OH)3(H2O)3V4O10]15+. A central bismutate/vanadate-mixed core comprises three sets of two types of the BiO6 pentagonal pyramid, the edge-sharing VO5 square-pyramidal triad, and a VO4 tetrahedron.  相似文献   

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