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991.
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
992.
草酸钴原位催化高氯酸铵热分解的DSC/TG-MS研究 总被引:5,自引:0,他引:5
采用差示扫描量热/热分析-质谱(DSC/TG-MS)联用技术研究了草酸钴对高氯酸铵的原位催化. 结果表明,草酸钴原位分解生成的钴氧化物对高氯酸铵有较强的催化作用,添加2%的草酸钴使高氯酸铵的分解温度降低104 ℃, 分解放热量从655 J/g增大到 1 469 J/g. 分解的气相产物主要有H2O, NH3,O2,HCl,Cl2,NO,N2O和NO2. 由于氧在新生态的纳米钴氧化物表面形成过氧化活性离子(O-2), 使氨氧化在钴氧化物的过氧化表面活性中心进行,加速了高氯酸铵的热分解,使其表观放热量大幅度增加. 相似文献
993.
A titanocene-ferrocenyl complex, (5-ferrocenyl-2-hydroxybenzenecarboxylato- O,O′)-bis(methylcyclopentadienyl)titanium(IV) 4, and an unexpected ionic complex, [C7H8NO3]- [(C5H5)Fe(C5H4)SO3]·H2O3 were synthesized and characterized by IR, ^1H NMR and elemental analysis. Compound 3 is of triclinic, space group P1 with a = 5.954(2), b = 13.208(5), c = 13.252(5) A, α = 60.993(7),β = 84.342(8),γ = 86.933(8)°, Z = 2, V = 906.8(6)A^3, Dc = 1.601 g/cm^3, μ(MoKα) = 0.987 mm^-1, F(000) = 452, the final R = 0.0647 and wR = 0.1333 for 2311 observed reflections (I 〉 2σ(I)). Compound 4 belongs to the monoclinic system, space group P2 1/c with α = 14.3310(9), b = 12.5065(8), c = 12.9406(10) A, β = 95.101(4)°, Z = 4, V = 2310.2(3) A^3, Dc = 1.513 g/cm^3, μ(MoKα) = 1.004 mm^-1, F(000) = 1088, the final R = 0.0461 and wR = 0.1048 for 2112 observed reflections (1 〉 2σ(I)). 相似文献
994.
TS-1分子筛Lewis酸性的理论研究 总被引:1,自引:0,他引:1
应用密度泛函理论和量子力学与分子力学联合的ONIOM2方法对含Ti的MFI分子筛(TS-1)中Ti4+离子在三种不同骨架落位上所表现的Lewis酸性进行了理论研究. 利用碱性探针分子(CO, NH3, 乙腈和吡啶)在骨架Ti活性中心的吸附作用,对吸附络合物的几何结构和吸附能进行了计算,并通过自然键轨道(NBO)分析考察了吸附络合物的电子结构. 结果表明,骨架Ti在T12位表现出明显的Lewis酸性,对NH3分子有较强的吸附作用. NBO分析表明,骨架Ti活性中心的Lewis酸性是由于 Ti - O 键的空σ反键轨道接受碱性探针分子提供的孤对电子;NH3分子吸附导致Ti4+离子由近正四面体中心对称变为五配位的三角双锥对称. 相似文献
995.
LV Zhi-Liang WANG Tian-Tian ZHANG Yi-Kai FENG Ji-Lu SUN Hai-Ling LIU Jia LIKe 《结构化学》2009,28(12):1640-1644
The title compound (Z)-1-(3-fluorobenzyl)-5-((3-fluorobenzylimino)(2-hydroxy-4- methoxyphenyl)methyl)pyridin-2(1H)-one (C27H22F2N2O3,Mr = 460.47) was synthesized and crystallized. The crystal belongs to the triclinic system,space group P1 with a = 9.951(6),b = 10.059(6),c = 12.927(7)A,α = 109.828(7),β = 102.304(7),γ = 104.898(7)°,Z = 2,V = 1110.2(11)A^3,Dc =1.377 Mg/m^3,μ(MoKα) = 0.102 mm^-1,F(000) = 480,the final R = 0.0449 and Rw = 0.1250 for 4595 observed reflections (I 〉 2σ(I)). X-ray analysis reveals that both m-fluorobenzyl groups are diorientationally disordered because of the rotation of C–C single bond which was represented as F(1),F(2) and F(1'),F(2'). The diorientational disorder was refined and gave the occupancies of 0.665(4) and 0.335(4) for F(1) and F(1'),0.631(3) and 0.369(3) for F(2) and F(2'). Hydrogen bonds existing in the cell link different components to stabilize the crystal structure. The active data proved that the title compound has good anti-HBV activity. 相似文献
996.
SUN Jian-Ke JIN Xu-Hui LI Wei ZHANG Jie 《结构化学》2009,28(11):1509-1512
A novel coordination polymer {[Mn(m-cpdba)(H2O)4]·H2O}n 1 has been synthesized and characterized. Single-crystal X-ray diffraction analysis reveals that compound 1 contains one-dimensional single-stranded helical chains, in which the chirality of a stereochemically labile amine of the ligands can be locked by the Mn(II) ion via coordination bonds and transferred to the whole coordination polymeric chain, exhibiting an identical absolute configuration. Crystal data for 1: C14H17Mn1N3O13, Mr = 490.25, space group C2/c, a = 18.5177(18), b = 6.6194(5), c = 31.563(4)A, β = 105.046(5)°, Z = 8, V = 3736.2(7)A^3, Dc = 1.743 g/cm^3, F(000) = 2008 and μ = 0.786 mm^-1. 相似文献
997.
WU Xiao-Yuan KUANG Xiao-Fei YU Rong-Min LU Can-Zhong 《结构化学》2009,28(11):1513-1518
A three-dimensional supramolecular architecture, {[Co(proH)(H2O)3]2[P2Mo5O23]}·7H2O (1, pro = praline), has been synthesized and characterized by IR, elemental analysis, thermogravimetric analysis, and single-crystal X-ray diffraction. 1 crystallizes in monoclinic, space group C2 with a = 20.600(3), b = 11.6980(11), c = 9.2944(10)A, β = 107.837(4)°, V = 2132.1(4) A^3, Z = 2, C10H46Co2Mo5N2O40P2, Mr = 1493.99, Dc = 2.327 g/cm^3, F(000) = 1468, μ(MoKα) = 2.375 mm^-1, the final R = 0.0339 and wR = 0.0844 for 4169 observed reflections with I 〉 2σ(I). Singlecrystal X-ray crystallographic analysis reveals that the helical water chains and {[Co(proH)- (H2O)3]2[P2Mo5O23]}n chains are perpendicular to each other and extend into an overall three-dimensional supramolecular architecture by hydrogen-bonding interactions. The magnetic investigation indicates weak antiferromagnetic interactions in the compound. 相似文献
998.
A new borate [H2EG][B7O10(OH)3] (1) based on [B14O20(OH)6]4- polyborate anions has been solvothermally synthesized in the presence of H2EG as a template (EG = ethylene glycol). The structure was determined by single-crystal X-ray diffraction and further characterized by FFIR, elemental analysis and thermogravimetric analysis. Compound 1 crystallizes in the triclinic system, space group Pi, with a = 8.5095(4), b = 8.8694(4), c = 10.0756(4) A, a = 95.094(2), β = 96.936(2), γ = 116.844(2)°, V = 664.66(5) A3. The structure of 1 consists of [B14O20(OH)6]4- moiety, which could be regarded as the largest isolated polyborate anion so far. The anions are interlinked via hydrogen bonding to form a 3D supramolecular network, whereas the diprotonated [H2EG]2+ are filled in the free space of inorganic borate network and interact with the inorganic framework by extensive hydrogen bonds. It is noteworthy that the EG acts not only as a solvent, but also as a template. 相似文献
999.
Two novel diethyltin(IV) complexes of N-salicylidenevaline (H2L1) and N-Sali- cylidenetryptophan (H2L^2), Et2SrtL^1 1 and Et2SnL^2 2, were synthesized and characterized by elemental analysis, IR, ^1H NMR and X-ray single-crystal diffraction analysis. Complex 1 belongs to the trigonal system, space group R-3 with a = b = 19.2730(5), c = 23.6890(13)A^°, V= 7620.4(5) A^°^3, Z = 6, Dc= 1.553 g/cm^3,μ= 1.518 mm^-1, F(000) = 3600, R = 0.0238 and wR = 0.0636. Complex 2 is of monoelinie system, space group P21/c with a = 13.7550(8), b = 11.5425(7), c = 12.7876(7)A^°, β= 93.585(1)°, V = 2026.3(2) A^°^3, Z = 4, Dc= 1.548 g/cm^3,μ = 1.286 mm^-1, F(000) = 976, R = 0.0298 and wR = 0.0722. Complex 1 is a cyclic trimer with a macrocyclic 12-membered ring structure formed by the bidentate bridging coordination of carboxylate group to tin atoms. The tin atom is six-coordinated in a distorted octahedral geometry. In complex 2, the distorted trigonal bipyramidal Et2SnL2 units are linked into polymeric chains by the weak Sn…O interaction involving Sn and the earbonyl O of an adjacent ligand, and the chains are further connected by intermolecular N-H…O hydrogen bonds to form a two-dimensional supramolecular structure. 相似文献
1000.
2-(4-Decarboxydehydroabietyl)-5-p-toyl-[1,3,4]-oxadiazole, C28H34N2O, has been synthesized and characterized by IR, NMR, elemental analysis and single-crystal X-ray diffraction method. The crystal belongs to the orthorhombic system, space group P212121 with a = 6.1351(5), b = 14.8495(19), c = 25.9050(2) A, V = 2360.0(4) A3, Z = 4, Mr = 414.57, Dc = 1.167 Mg/m^3, 2 = 0.71073 A,μ(MoKa) = 0.070 mm^-1, F(000) = 896, the final R = 0.0452 and wR = 0.1076 for 1647 observed reflections with I 〉 2σ(I). There are five rings in the crystal structure of the title compound, but the oxadiazole ring is non-coplanar with the benzene ring D. 相似文献