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1.
The complex has been synthesized and characterized by spectroscopic techniques and single-crystal X-ray analysis. The crystal is orthorhombic , space group P212121 with a=1.6620(3)nm, b=1.7300(4)nm, c=0.5450(1)nm and Z=4. In the crystal lattice, the molecules create a two-dimensional network structure through hydrogen bonds. The C-H…O intermolecular hydrogen bonds connect the title complex to form layer super-molecular plane structure perpendicular to the axis b, with the layers stacked by the Van der Waals interaction. CCDC: 195309.  相似文献   

2.
Seeing stars: The two-dimensional patterns of the polycyclic heteroaromatic star molecules 1 on graphite vary with the side chain length. For n=12, frustrated self-assembly leads to hierarchically organized superstructures: up to 10?molecules form triangular aggregates which pack densely into hexagonal patterns with very large (15.5?nm) lattice constants.  相似文献   

3.
Sodium salts of water‐soluble polymers poly{[2,5‐bis(3‐sulfonatopropoxy)‐1,4‐phenylene]‐alt‐[2,5‐bis(hexyloxy)‐1,4‐phenylene]} ( P1 ), poly{[2,5‐bis(3‐sulfonatopropoxy)‐1,4‐phenylene]‐alt‐[2,5‐bis(dodecyloxy)‐1,4‐phenylene]} ( P2 ), poly{[2,5‐bis(3‐sulfonatopropoxy)‐1,4‐phenylene]‐alt‐[2,5‐bis(dibenzyloxy)‐1,4‐phenylene]} ( P3 ), poly[2‐hexyloxy‐5‐(3‐sulfonatopropoxy)‐1,4‐phenylene] ( P4 ), and poly[2‐dodecyloxy‐5‐(3‐sulfonatopropoxy)‐1,4‐phenylene] ( P5 )] were synthesized with Suzuki coupling reactions and fully characterized. The first group of polymers ( P1 – P3 ) with symmetric structures gave lower absorption maxima [maximum absorption wavelength (λmax) = 296–305 nm] and emission maxima [maximum emission wavelength (λem) = 361–398 nm] than asymmetric polymers P4 (λmax = 329 nm, λem = 399 nm) and P5 (λmax = 335 nm, λem = 401 nm). The aggregation properties of polymers P1 – P5 in different solvent mixtures were investigated, and their influence on the optical properties was examined in detail. Dynamic light scattering studies of the aggregation behavior of polymer P1 in solvents indicated the presence of aggregated species of various sizes ranging from 80 to 800 nm. The presence of alkoxy groups and 3‐sulfonatopropoxy groups on adjacent phenylene rings along the polymer backbone of the first set hindered the optimization of nonpolar interactions. The alkyl chain crystallization on one side of the polymer chain and the polar interactions on the other side allowed the polymers ( P4 and P5 ) to form a lamellar structure in the polymer lattice. Significant quenching of the polymer fluorescence upon the addition of positively charged viologen derivatives or cytochrome‐C was also observed. The quenching effect on the polymer fluorescence confirmed that the newly synthesized polymers could be used in the fabrication of biological and chemical sensors. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 3763–3777, 2006  相似文献   

4.
合成了一种新的铜配合物[Cu2(μ-2-atp)(phen)4].2ClO4(2-atp为2-氨基对苯二甲酸,phen为邻菲咯啉),利用红外光谱和X射线单晶衍射表征了产物的结构,利用元素分析测定了其元素组成,利用热重分析考察了其热分解行为.结果表明,标题化合物属于三斜晶系,P-1空间群,晶胞参数为:a=0.971 0(9)nm,b=1.187 8(1)nm,c=1.234 9(1)nm,α=70.104 0(1)°,β=68.699 0(1)°,γ=86.719 0(1)°,V=1.244 1(2)nm3,Z=1,Dc=1.635g/cm3,μ=1.041mm-1,F(000)=623,R1=0.058 4,wR2=0.129 3.该化合物具有双核铜结构,通过强烈的π-π堆积作用形成二维超分子结构.  相似文献   

5.
以硝酸锌、樟脑酸(H2CAM)和1,2-二咪唑基二甲苯(obix)或4,4′-二咪唑基二甲联苯(bimb)为原料,在水热条件下得到2个结构不同的配位聚合物[Zn(obix)(CAM)]n(1)和[Zn(bimb)(CAM)]n(2)。对它们进行了元素分析、红外光谱和热重等分析,并利用X-射线洐射测定了它们的单晶结构。配合物1中2个锌离子通过2个obix配体桥连成一个24元大环,它再通过CAM配体连接成一维管状结构,而配合物2中锌离子通过两种配体桥连成二维层状结构。结果说明了辅助配体在配合物组装过程中起着非常重要的作用。此外还研究了它们的荧光性质。  相似文献   

6.
红霉素分子印迹二维光子晶体水凝胶传感器的研究   总被引:1,自引:0,他引:1  
以红霉素为印迹分子,聚苯乙烯二维光子晶体为模板,甲基丙烯酸为功能单体,乙二醇二甲基丙烯酸甲酯为交联剂,2,2-二乙氧基苯乙酮为引发剂,紫外光引发聚合,在甲醇-乙酸(9∶1, V/V)中洗脱印迹分子,得到能够特异性识别红霉素的分子印迹二维光子晶体水凝胶.通过测试德拜环直径变化,研究了此水凝胶在红霉素溶液中的响应性能.实验结果表明,当红霉素的浓度从0增加到1×10-6 mol/L时,德拜环直径增加6 mm, 相应的晶格间距减小30 nm.此外,水凝胶在1×10-6 mol/L红霉素的类似物罗红霉素、琥乙红霉素溶液中,德拜环直径仅分别增加1.5和2.0 mm,表明此光子晶体水凝胶具有良好的选择性,有望用于红霉素低成本的简易检测.  相似文献   

7.
A title organic-inorganic hybrid material 2-amino-3-benzyloxy pyridinium perchlorate was synthesized by slow evaporation at room temperature using 2-amino-3-benzyloxypyridine as the structure-directing agent. The structure of the title compound was determined by means of single-crystal X-ray diffraction at 293 K. The results show that this compound crystallizes in the centrosymetric monoclinic system with a space group of P21/n and lattice parameters of a=0.7025(5) nm, b=1.2635(5) nm, c=1.5766(5) nm, Z=4 and V=1.3905(2) nm3. The crystal structure has been determined and refined to R1=0.0367 and wR2=0.1022 using 2326 independent reflections and can be described as a succession of organic and inorganic layers parallel to the bc plane. In this arrangement, hydrogen bonds and van der Waals interactions between different species play an important role in the two-dimensional(2D) network cohesion. This compound was also characterized by means of infrared spectroscopy, Raman spectroscopy and thermogravimetric analysis-differential thermal analysis(TG-DTA). Moreover, protonic conduction of this compound determined by an impedance analyzer has been studied in the temperature range of 303-373 K.  相似文献   

8.
Self-assembled monolayer of two azobenzene-derived alkanethiols with different terminal alkyl chain lengths (shortly as C8C3SH and C1C4SH) on gold were studied using atomic force microscopy. The C8C3SH SAMs showed a very regular packing structure with a lattice constant of a=0.57±0.04 nm, b=0.73±0.06 nm and θ=120±10°, mainly domianted by the terminated alkyl chains. On the other hand, the C1C4SH SAMs exhibited a number of different packing domains on the gold surface. The closest packing lattice was a=0.37±0.04 nm, b=0.47±0.02 nm, and θ=,107±6°, most probably representing the aggregation of azobenzene chromophoren. Another two typical lattices observed were a=0.65±0.03 nm, b=0.72±0.03 nm, θ=120±2°, and a=0.47±0.03 nm.b=0.47±0.03 nm.θ=100±10°, respectively. The packing structure of C1C4SH monolayers on gold is believed to be dominated by the azobenzene chromophore.  相似文献   

9.
The copolymeric gel films were prepared by a radical copolymerization of stearyl acrylate(SA), acrylic acid(AA) and N,N′-methylenebisacrylamide (MBAA) as a cross-linking agent. The copolymeric (molar ratio SA/AA/MBAA: 24.7/74.3/1.0) gel films with crystalline side chains were swollen in three different kinds of solvent and their aggregation structure and responsive properties have been investigated. In order to control the SA side chains-solvent interaction and to dissociate carboxyl groups in AA, solvents such as dimethyl sulfoxide (DMSO), (1-hexanol/DMSO) mixed solvents and water with different pH values were used. The responsive behaviors of the (SA/AA/MBAA) gel film swollen in different solvents were discussed on the basis of the weight swelling ratio. The X-ray diffraction study of the gel film revealed that the long period corresponding to a layer distance for the (SA/AA/MBAA) gel film swollen in DMSO increased with temperature or the swelling ratio, and the interchain distance of alkyl side chains remained constant with the variation of temperature up to the melting temperature of SA side chain crystals. The swelling ratio of the gel film in (1-hexanol/DMSO) mixed solvent exhibited an abrupt increase in the case of about 40wt% of 1-hexanol, because the SA side chain crystals of the gel film in the mixed solvents were dissolved due to an increase in SA-solvent interaction. On the other hand, the gel film in the water with different pH values showed a sharp increase in the swelling ratio above pH = 11, because the ionic repulsive force among the AA groups became greater than the aggregation one among alkyl side chains. These results indicate that the swelling ratio of the (SA/AA/MBAA) gel film can be controlled by temperature, pH and the magnitude of solubility parameter of swelling solvent.  相似文献   

10.
以去叔丁基硫杂杯[4]芳烃与Mn(II)为研究对象,通过改变体系溶剂分别得到了两个四核化合物Mn4(T4A)2 (1)和Mn4(T4A)2(DMF)2(2) (T4A = thiacalix[4]arene)。当反应溶剂为氯仿(CHCl3)和甲醇的混合溶剂时,形成的是以四核锰为结构单元的二维“笼目”(Kagomé)状超分子化合物1,而当反应溶剂为N,N-二甲基甲酰胺(DMF)和甲醇的混合溶剂时,得到的是格子状二维超分子互穿的三维结构化合物2。化合物1具有很大的溶剂占有空隙,是一个潜在的多孔材料,而化合物2是一个紧密堆积的拓展结构。  相似文献   

11.
报道了2-(甲苯-4-磺酰胺基)-苯甲酸(I)的元素分析和红外、核磁共振光谱性质并通过单晶X射线衍射确定了其晶体结构. 晶体属单斜晶系, 空间群为C2/c,晶胞参数为, a=2.7320(3) nm, b=0.85441(8) nm, c=1.17607(11) nm, α=90°, β=98.728(3)°, γ=90°, V=2.7135(5) nm3, Z=8. 晶体中分子单体通过N—H…O 和O—H…O氢键作用形成具有中心对称的二聚体, 且进一步通过两种不同的C—H…O 氢键和π…π作用形成超分子结构. 在不同的溶剂中, 化合物I的紫外吸收表现出明显的溶剂效应, 此外, 荧光光谱与DSC-TGA热重分析表明, 该化合物是一种耐热的荧光材料.  相似文献   

12.
Na(NTO)(H2O)的制备、晶体结构及热力学性质研究   总被引:6,自引:0,他引:6  
利用氢氧化钠溶液与NTO水溶液进行反应制备了标题化合物并培养出单晶。通过X射线单晶结构分析法测定分子结构和晶体结构,其分子式可表示为Na(NTO)(H2O),晶体属单斜晶系,P21/c空间群,晶体学参数为:a=0.6303(1)nm,b=0.8285(1)nm,c=1.1574(2)nm,β=103.85(1)°,V=0.5868(2)nm^3,Dc=1.925g/cm^3,Z=4,F(000)=344,μ=0.238mm^-1,R=0.0259。通过Na(NTO)(H2O)在水中溶解焓的测定,算得其标准生成焓、晶格焓和晶格能。  相似文献   

13.
Aqueous solutions of five ionic liquids (ILs) of the 1-n-alkyl-3-methylimidazolium bromide family, [C(n)mim]Br (n = 4, 6, 8, 10, 12), were investigated by NMR measurements at 298.2 K as a function of IL concentrations. Critical aggregation concentrations and aggregation numbers of these ILs were determined by 1H NMR except for [C4mim]Br in D2O. The effects of the alkyl chain length of the cations were examined on the aggregation behavior of the ILs. 1H NMR data of the solvent D2O were used to investigate the hydration of the ILs in D2O, and it was found that the ionic hydration and the cation-anion association or aggregation of the ILs offset each other. The microenvironment of different protons of cations of the ILs in the aggregates was probed by determining the spin-lattice relaxation rate (1/T1). It is suggested that the imidazolium rings in the aggregates are exposed to water and that the molecular motion of the aggregates is more restricted than that of the monomers of the ILs. Furthermore, a stair-like microscopic aggregation structure is suggested for the [C(n)mim]Br/D2O (n = 6, 8, 10) systems from 2-D 1H-1H NOESY measurements.  相似文献   

14.
配合物{[Cu(hmtade)][Ni(dmit)2]}2·4DMSO的合成、表征及晶体结构   总被引:1,自引:1,他引:0  
合成了配合物{[Cu(hmtade)][Ni(dmit)2]}2·4DMSO(1)(hmtade为5,7,7,12,14,14-六甲基-1,4,8,11-四氮杂环十四-4,11-二烯; dmit为1,3-二硫杂环戊二烯-2-硫酮-4,5-二硫醇; DMSO为二甲亚砜), 采用元素分析、红外光谱和紫外-可见光谱进行了表征, 并用X射线衍射法测定了晶体结构. 该晶体属于单斜晶系, P21/n空间群; 晶胞参数: a=1.49952(6) nm, b=1.77229(7) nm, c=3.1275(1) nm, β=102.442(1)°, V=8.1163(5) nm3, Dc=1.558 Mg/m3, Z=8, F(000)=3944, μ(Mo Kα)=1.637 mm-1, S=1.016, (Δ/σ)max=0.001, R1=0.0673, wR2 =0.1672[I>2σ(I)]. 晶体结构研究表明, 配合物{[Cu(hmtade)]·[Ni(dmit)2]}2·4DMSO包含2个[Cu(hmtade)][Ni(dmit)2]子单元. 每个子单元中, 1个dmit中的1个S原子与Cu及Ni配位, 形成异双核Cu—Ni配合物. 其中Cu(Ⅱ)为五配位的四方锥构形, Cu—N键长在0.1949(5)~0.2007(4) nm范围内, Cu—S键长分别为0.28913(18)和0.28952(18) nm; 配阴离子[Ni(dmit)2]2-为畸变四方形, Ni—S键长在0.21729(16)~0.21905(17) nm范围内. 溶剂分子DMSO与配体hmtade形成了N—H…O氢键. 通过分子内S…S和S…H短接触形成了二聚体, 二聚体之间通过S…S短接触形成一维链状结构, 并通过S…S, S…H和C…H短接触进一步形成二维和三维结构.  相似文献   

15.
A series of six perylene bisimides (PBIs) with hydrophilic and hydrophobic side chains at the imide nitrogens were applied for a comparative study of the solvent and structural effects on the aggregation behaviour of this class of dyes. A comparison of the binding constants in tetrachloromethane at room temperature revealed the highest binding constant of about 10(5) M(-1) for a PBI bearing 3,4,5-tridodecyloxyphenyl substituents at the imide nitrogens, followed by 3,4,5-tridodecylphenyl and alkyl-substituted PBIs, whereas no aggregation could be observed in the accessible concentration range for PBIs equipped with bulky 2,6-diisopropylphenyl substituents at the imide nitrogens. The aggregation behaviour of three properly soluble compounds was investigated in 17 different solvents covering a broad polarity range from nonpolar n-hexane to highly polar DMSO and water. Linear free energy relationships (LFER) revealed a biphasic behaviour between Gibbs free energies of aggregation and common empirical solvent polarity scales indicating particularly strong π-π stacking interactions in nonpolar aliphatic and polar alcoholic solvents whilst the weakest binding is observed in dichloromethane and chloroform. Accordingly, PBI aggregation is dominated by electrostatic interactions in nonpolar solvents and by solvophobic interactions in protic solvents. In water, the aggregation constant is increased far beyond LFER expectations pointing at a pronounced hydrophobic effect.  相似文献   

16.
The inverse opal hydrogel heterostructure (polyacrylamide (PAAm) (left side)-polyacrylic acid (PAA)/PAAm interpenetrating polymer network (IPN) (right side) is created by colloidal crystal templating. The two parts, PAAm and IPN, appear different structural colors due to the varied lattice constants and solvent response behaviors. The IPN part keeps red color and PAAm part shows different colors when the composition of the mixed solvent (ethanol and water) and crosslinking degree are changed. For example, as the ethanol content in the mixed solvents increases from 0% to 70%, the PAAm part color changes from red, yellow, green to blue when the PAAm crosslinking degree is 5 mol% or 1 mol%. Meanwhile, a large blue shift of about 200 nm can be realized covering almost the entire wavelength of visible light due to the decreased lattice spacing induced by the PAAm shrinkage. Thus, multi two-color patterns can be realized by changing the color of PAAm and the color of IPN remain red as background for contrast. Moreover, the IPN part can change from red to green by reducing the PAAm infiltration time in IPN part, which can realize the change from two-color pattern to one-color pattern at green region.  相似文献   

17.
雷声  张晶  黄建滨 《物理化学学报》2007,23(11):1657-1661
采用表面张力测定法和核磁共振谱等方法研究了阴离子表面活性剂十二烷基硫酸钠(SDS)在水溶性室温离子液体[BMim]BF4/水混合溶剂中的表面性质及聚集行为, 发现极少量[BMim]BF4的介入就可以显著降低SDS的临界胶束浓度, 提高体系的表面活性; 且[BMim]BF4在混合溶剂中所占的摩尔分数(x1)在一定范围内(0相似文献   

18.
张登  吕赟  许新  丁少华  许岩 《无机化学学报》2012,28(6):1298-1304
本文分别采用水热和溶剂热的方法,以乙二胺和哌嗪为有机模板剂分别合成了两种新的三维孔道结构的稀土硫酸盐[Gd2(SO4)5(H2O)2][C2N2H10]2(1),[Eu2(SO4)5(H2O)2][C4N2H12]2(2),并且通过单晶X射线衍射、元素分析、红外、热重对两种化合物进行了表征。化合物1和2都属于单斜晶系,P21/c空间群。化合物1:a=0.652 1(4)nm,b=1.692 0(9)nm,c=2.023 3(11)nm,β=95.168(7)°,Z=4。化合物2:a=1.972 1(2)nm,b=1.927 1(2)nm,c=1.323 20(14)nm,β=92.307 0(10)°,Z=8。单晶结构分析表明,这两种化合物的无机骨架都是由SO4连接具有交替十六元环与八元环二维层形成的三维孔道结构。化合物2的固体荧光分析表明,在396 nm的激发波长下表现出Eu3+的特有发光性质。  相似文献   

19.
Communication: The surfaces of single faceted crystals of a thermotropic liquid crystalline poly(aryl ether ketone) copolymer containing chloro‐side group are investigated by atomic force microscope. The molecular lattice resolution images of the single faceted crystals indicate that the surfaces of the crystals consist of molecular chain ends of the copolymer, and the crystals exhibit orthorhombic packing with the unit cell dimensions of a = 0.787 ± 0.020 nm and b = 0.625 ± 0.010 nm, respectively. The data are further confirmed by electron diffraction results.  相似文献   

20.
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