313 resultados para R-0


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A charge transfer salt, (Bu4N)(4) (C5H6)[(HSiMo11MoO40)-Mo-VI-O-V] has been photochemically synthesized from (Bu4N)(4)SiMo12O40 and 1.3-cyclopentadiene and Characterized, by elemental analysis, IR spectra, solid diffusion reflectance electronic spectra, CV and ESR. The X-ray crystal structure revealed that the title complex crystal data are as follows: triclinic, space group P (1) over bar, a = 14.347(3), b = 14.423(3), c = 27.158(5) Angstrom, alpha = 96.90(3), beta = 104.18(3), gamma = 98.20(3)degrees, V = 5322(2) Angstrom (3), Z = 2, M-r = 2855. 30, D-c = 1.782g.cm(-3), F(000) = 2860, R = 0.0719, wR = 0.198. The title compound is composed of 1.3-cyclopentadiene, four tetrabutylammonium and [(SiMo11MoO40)-Mo-VI-O-V](4-) anion.

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A new molybdenum-citrato cluster containing [Mo2O2(mu-S)(2)(C6H5O7)(C6H4O7)](5-) anion was synthesized and characterized by elemental analysis, IR, UV-Vis spectra, XPS and X-ray diffraction. The parameters of the crystal structure of the compound are monoclinic, space group P2(1)/c, a = 2. 376 6(5) nm, b = 1. 327 4(3) nm, c = 2. 247 1(5) nm, beta = 118. 21 degrees, V = 6. 247(2) nm(3), Z = 8, D-c = 2. 128 g/cm(3), F(000) = 3 984, mu = 1 694 cm(-1), R = 0. 083 1 and R-2,R-w = 0. 154 9. The anion is binuclear molybdenum-citrato complex with mu(2)-S bridge. Each molybdenum atom pocesesses a distorted octahedral struture, which is coordinated with a terminal oxygen, two sulfur atoms, three oxygen atoms of hydroxyl, alpha-carboxylate, beta-carboxylate from citrate.

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Crystal and molecular structure of (2.6-dipropylphenylamide) dimethyl (tetra-methyl cyclopentadienyl) silane titanium dichloride (I) was fully characterized by X-ray diffraction. The crystal is obtained from a mixture of ether/hexane as orthorhombic. with a = 12.658 (3) Angstrom. b = 16.62 (3) Angstrom. c = 11.760 (2) Angstrom. V = 2474.2 (9) Angstrom(3). Z = 4, space group Pnma. R = 0.0399; Componud I compose of the pi-bounded ring with its dimethylsilyl-dipropyl phenyl amido group and the two terminal chloride atoms coordinated to central metal to form a so-called constrained geometry catalyst (CGC) structure. The result of molecular mechanics (MM) calculations on compound I shows that bond lengths and bond angles from the MM calculation are comparable to the data obtained from the X-ray diffraction study. The relation of the structure of CGCs and their catalytic activity by MM calculations is also discussed.

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The reaction of NdCl3 with 2 equiv. of Na-(BuC5H4)-C-t in THF(tetrahydrofuran) gives blue crystals [((BUC5H4)-C-t)(2)NdCl](2), C36H52Cl2Nd2(M-r = 844.11) Which crystallizes in the triclinic system with space group . The crystal data are a=11.978 (1), b=12.671(4), c=12.706(2)Angstrom, alpha=105.47(2), beta=99.38(1)? gamma=93.15 (2)degrees, V=1825 (3) Angstrom(3), Z = 2 , D-c = 1.53g/cm(3), F(000) = 450 , T = 298K , lambda(MoK alpha) = 0.71069 Angstrom, , mu = 14.97cm(-1). Final R = 0.0390, R-w = 0.0376 for 4329 reflections with I greater than or equal to 3 sigma(I-o). The molecule has a dimer structure with two certrosymmetrical chlorine bridges. The structural trend of these analogous complexes is discussed.

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Nine triphenyltin - 2 - (1,2 - ethylenedithio) methylene - 3 - oxo - 5 - aryl - 4 - pentenicates were synthesized. The crystal structure of the title compound 3b (C33H28O3S2Sn) was determined by X - ray diffraction analysis. The crystal belongs to triclinic system, space group P(1)overbar with a = 0.9074 (2) nm, b = 1.6809(3)nm, c = 2.1834(4)nm, alpha =77.57(3)degrees, beta = 88.04(3)degrees, gamma = 89.47(3)degrees, V = 3.2503nm(3), Z = 2, R = 0.0592. In crystal of 3b, there exist intramolecular 0-Sn coordination bonds, with carboxylate group acting as a bidentate ligand: Sn(1)-0(1) = 0.2086(5) and Sn(1)-0(2) = 0.2594nm, having a deformed trigonal bipyramidal geometry.

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合成了含有Mo—S簇阴离子 [Mo2 O2 ( μ S) 2 (C6H5O7) (C6H4 O7) ]5-柠檬酸簇合物 ,并通过元素分析、红外光谱、紫外 可见光谱和X射线光电子能谱对配合物进行了表征 ,用X射线衍射法测定了该化合物的晶体结构 .结果表明 ,该簇合物属于单斜晶系 ,空间群P2 1/c,a =2 3 766( 5)nm ,b =1 3 2 74 ( 3 )nm ,c =2 2 4 71 ( 5)nm ,α=γ =90°,β=1 1 8 2 1°,V =6 2 4 7( 2 )nm3 ,Z =8,一致性因子R =0 0 83 1 ,R2 ,w=0 1 536.该簇合物阴离子中每一个Mo原子都采取扭曲的八面体结构 ,柠檬酸通过羟基、α 羧基、一个 β 羧基与Mo配位 .晶体结构表明在一个结晶学上不对称的结构单元内有两个结晶学上独立的分子.

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由2-(1,2-亚乙二硫)亚甲基-3-羰基-5-芳基-4-戊烯酸与三苯基氢氧化锡反应,合成了九个标题化合物3.用X射线衍射法测定了3b的晶体结构.该晶体属三斜晶系,空间群Pl,α=0.9074(2)nm,b=1.6809(3)nm,c=2.1834(4)nm,α=77.57(3)°,β=88.04(3)°,γ=89.47(3)°,V=3.2503nm~3,Z=2;R=0.0592.由锡氧原子间距离可推测,该晶体中羧酸根作为双齿配体与锡原子形成了分子内五配位结构.

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以环戊二烯与 1 2 钼硅杂多四丁基铵为原料 ,采用光化学法合成了一种新型电荷转移盐 (Bu4N) 4(C5 H6 ) [HSiMoVI11MoVO40 ]。用元素分析、IR、CV、固体漫反射电子光谱、ESR进行了表征。X 射线晶体结构测定其晶体属三斜晶系 ,空间群P1 ,晶胞参数a =1 4.347(3) ,b =1 4.42 3(3) ,c =2 7.1 5 8(5 ) ,α =96 .90 (3) ,β =1 0 4.1 8(3) ,γ =98.2 0 (3)° ,V =5 32 2 (2 ) 3,Z =2 ,Mr=2 85 5 .30 ,Dc=1 .782 g·cm-3,F(0 0 0 ) =2 86 0 ,R =0 .0 71 9,wR =0 .1 983。标题化合物由 1个环戊二烯、4个Bu4N+阳离子和 1个 [SiMoVI11MoVO40 ]4 -阴离子构成。

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When the aggregation of C-60 is arranged in mono-dispersed state on the ITO substrate, the photoluminescence (PL) spectra are observed clearly. These emission peaks are attributed to recombination of self - trapped excitons, the zero-phonon exciton (R-0) and its phonon replicas.

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A novel layered compound, [Ni(C10H8N2)(2)V3O8.5], was hydrothermally synthesized and structurally characterized by single crystal X-ray diffraction. The compound crystallizes in monoclinic system, space group P21/c with a = 1.551 8(3) nm, b = 1.476 1(3) nm, c = 1.048 3(2) nm, beta = 92.02(3), V = 2.399 8(8) nm(3), Z = 4, R = 0. 046 7, wR(2) = 0. 085 9.

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The title supramolecular compound, [HMDH2][(H2PMoMo11O40)-Mo-V] . 2AA . 3H(2)O . DMF (HMD = hexamethylene diamine; AA=acetaldehyde; DMF=N,N-dimethyl formamide), has been photochemically synthesized by using elemental analysis, IR, solid diffusion reflectance, electronic spectra, ESR spectra and X-ray single-crystal analysis. The crystallographic data: triclinic, P (1) over bar, a=14.092(2), b=14.347(3), c=14.358(3)Angstrom, alpha = 75.10(3), beta = 80.70(3), gamma = 80.73(3)degrees, V = 2746.6(10)Angstrom (3), Z = 2, M-r = 2081.68, D-c=2.517g/cm(3), F(000) =1970, mu (MoK alpha) =2.766mm(-1). The structure has been refined to R =0.0832 and wR=0.2638, by full-matrix least-squares method. The title compound is composed of hexamethylene diamine, two acetaldehyde molecules, three water molecules, one N,N-dimethylformamide and [(H2PMoMo11O40)-Mo-V](2-) heteropoly anion.

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The first mononuclear tungsten-citrato complex, (NH4)(3)[Li(H2O)(3)WO3(C6H4O7)] (1) has been prepared by the reaction of ammonium tetrathio tungstate and lithium citrate in CH3OH - H2O solution at pH 8.2. There are two crystallographically independent anions in the asymmetric crystallographic unit. The crystal structure of the title compound (triclinic, space group P (1) over bar, a = 6.901(1), b = 15.136(3), c = 16.107(3) Angstrom, alpha = 75.85(3), beta = 89.89(3), gamma = 89.97(3), V = 1631.4(6) Angstrom (3), R = 0.068, R-w = 0.1674 for 3878 reflections with I > 2 sigma (1)), reveals that in the compound a tungsten atom is coordinated to a fully deprotonated citrate as a tridentate ligand and three terminal oxygen atoms to form a distorted coordination octahedron.

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(2,4-C7H11)(2)Yb . DME was synthesized by the reaction of YbCl3 with K(2,4-C7H11)(2,4-dimethylpentadienyl potassium), and the single crystal X-ray diffraction showed that the complex exists in a cis- staggered conformation. Thf crystal of the compound belongs to the monoclinic space group P2(1)/n with a = 0.675 2 (1) nm, b = 1.490 6 (1) nm, c = 1.529 3 (2) nm, beta = 97.55 (2)degrees, V = 1.977 79 (4) nm(3), Z = 4, F(000) = 735.8 e, mu = 49.49 cm(-1), R = 0.033 and R-w = 0.032. The title complex can be used as a catalyst for the polymerization of methyl methacrylate (MMA).

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Anhydrous SmCl3 reacts with two equal of Li(1-3-(Bu2C5H3)-Bu-t) to give a complex (1,3-(Bu2C5H3)-Bu-t)(2) Sm(mu -Cl)(2)Li(THF)(2) (C34H58Cl2LiO2Sm, M-r = 726.99), monoclinic, space group P2(1)/n, a = 10.615(2), b = 21.037(4), c = 17.166(3) Angstrom, beta = 93.60(3)degrees, V = 3825.7 (13) Angstrom (3), Z = 4, D-c = 1.262 Mg/m(3), mu = 1.699 mm(-1) and F(000) = 1508, final R = 0.0387 and wR = 0.0741 for 5320 observed[I greater than or equal to2 sigma (I)] reflections. The average Sm - C distance is 2.73 Angstrom. Sm - Cl1 and Sm - Cl2 distances are 2.719 (2) and 2. 697 (2) Angstrom, respectively. Two 1, 3-(Bu2C5H3)-Bu-t-ring centroids and two mu (2)-bridging chloride atoms around Sm atom form a distorted tetrahedron.

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以苯酚 (phenol)和对甲苯磺酸 (paratoluenesulfonicacid ,PTSA)的混合物为模拟样品 ,毛细管电泳检测了苯酚体中的对甲苯磺酸。考察了磷酸缓冲溶液的浓度和pH对分离的影响 ,选择桂皮酸作为内标 ,采用内标法和标准曲线法得到了对甲苯磺酸在 50mg/L苯酚基体中的标准曲线 ,其线性范围为1 2 5~ 1 2 .5mg/L (R =0 .9999) ,检测限为 0 .75mg/L (S/N =3) ,讨论了毛细管电泳中的基体效应 ,并应用标准加入法测定了 4个实际样品