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991.
一种新颖有机/无机杂化配位聚合物[(C7H18N)(Ag2I3)]n的合成、结构及量子化学计算(英) 总被引:1,自引:0,他引:1
A one dimensional coordination polymer, [(C7H18N)(Ag2I3)]n((C7H18N)+=Methyltriethylammonium) has been successfully synthesized and characterized by X-ray single-crystal diffraction method. Structure analysis shows that the compound consists of organic cations(Methyltriethylammonium) and inorganic anion chains (Ag2I3)n-. The inorganic moiety consists of AgI4 tetrahedron, which shares the same edges with adjacent AgI4 tetrahedrons to form one-dimensional infinite double chains along a-axis. There exists weak interaction among Ag…Ag atoms in the crystal. Anion chains are surrounded by Methyltriethylammonium cations. Anion chains and cations are in combination with each other by static attracting forces in the crystal to form so-called organic-inorganic hybrid structure. According to the crystal structure data, quantum chemistry calculation with DFT on B3LYP level was used to reveal the electronic structure of title compound. CCDC: 254288. 相似文献
992.
Megumi Mizuno Masahide Takahashi Yomei Tokuda Toshinobu Yoko 《Journal of Sol-Gel Science and Technology》2007,44(1):47-52
Organically-modified silicate-phosphate and silicate-phosphite copolymers were prepared through nonaqueous acid–base reaction.
The inductive effect of the organic substituent of the starting materials such as organically-modified chlorosilane and phosphorous
acid on the acid–base reaction was investigated by 31P NMR measurement and ab initio molecular orbital calculation. The condensation reaction takes place by nucleophilic addition
of phosphate ion (or phosphite ion) to chlorosilane through SN2 mechanism to form silicate-phosphate (or phosphite) network. The reactivity of the acid–base pair can be controlled by changing
the inductive effect of the organic substituents on the starting materials. 相似文献
993.
Ludmila úrková Renáta Kucsera Róbert Gyepes Michal Sivák 《Monatshefte für Chemie / Chemical Monthly》2003,134(8):1071-1079
Summary. Two novel compounds, [Co(phen)3]2V4O12·phen·22H2O (1) and [Ni(phen)3]2 V4O12·phen·22H2O (2), were prepared from KVO3–1,10-phenanthroline (phen)–Co(NO3)2, resp. NiCl2–H2O reaction systems. The compounds 1 and 2 are isomorphous and crystallize in triclinic system, space group P-1. Their crystal structures are formed by two types of layers parallel to 001: a cationic one consisting of [MII(phen)3]2+ ions and an anionic one containing the cyclic V4O12
4– anions. The solvate phenanthroline and crystal water molecules are located in the cationic and anionic layers, respectively. The IR spectra of 1 and 2 are consistent with the presence of the cyclic V4O12
4– anions in the complexes.Received November 13, 2002; accepted (revised) February 3, 2003
Published online June 2, 2003 相似文献
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Organic/Inorganic hybrid systems present a promising alternative for the creation of high-performance materials due to their biphasic structure that imparts multifunctional properties. The sol-gel process which initiated with the synthesis of inorganic glasses has now become a synthetic route for organic-inorganic assemblies due to several advantages such as mild processing conditions and the freedom to play with the structures of precursors. This versatility of the low-temperature sol-gel process provides an opportunity to engineer both the phases resulting in a synergistic combination or entirely new set of properties fruitful for different applications. This review highlights the several pathways for synthesis of silica particles, the interfacial modification and the classification of hybrid materials based on the method of incorporation of an inorganic moiety in the organic matrix along with the structure-property relationship, and the characterization to develop a fundamental understanding of the process. The nature of bonding between the two different species greatly affects the hybrid nanostructure and thus, the bulk properties of the system. In particular, acrylate/silica system has been focused due to its distinctive properties such as transparency, gloss, and strength that find large-scale application in the field of coatings, plastics and rubbers.Abbreviations: °: Degree; °C: Degree Celsius; 1H NMR: Proton nuclear magnetic resonance; A°: Angstrom; AHAS: N-(3-acryloxy-2-hydroxyl propyl)-3-amino-propyltriethoxysilane; AIBA: 2,2′-Azobis(2-methylpropionamidine) dihydrochloride; AIBN: 2,2′-Azobis(2-methylpropionitrile); Al: Aluminium; APDMES: Aminopropyldimethylethoxysilane; APTES: 3-Aminopropyltriethoxysilane; ATRP: Atom transfer radical polymerization; CERAMERS: Ceramically Modified Monomers; CTAB: Cetyltrimethylammonium bromide; DFMA: Dodecafluoroheptyl methacrylate; DMF: Dimethylformamide; DPSD: Diphenylsilanediol; FESEM: Field Emission Scanning Electron Microscope; FTIR: Fourier-transform infrared spectroscopy; GPTMS: 3-Glycidoxypropyltrimethoxysilane; HDTMS: Hexadecyltrimethoxysilane; HEMA: 2-Hydroxyethyl methacrylate; HLB: Hydrophilic-Lyophilic Balance; HMDS: Hexamethyldisilazane; HPC: Hydroxypropyl Cellulose; IPN: Interpenetrating Network; KPS: Potassium persulfate; LCST: Lower critical solution temperature; McPTMS: 3-Mercaptopropyltrimethoxysilane; MOI: 2-(methacryloyloxy)ethyl isocyanate; MPEGMA: Monomethoxy-capped poly(ethylene glycol) methacrylate; MPTMS: 3-methacryloxypropyltrimethoxysilane; MTC: 2-(methacryloyl) ethyltrimethylammonium chloride; MTES: Methyltriethoxysilane; MTMS: Methyltrimethoxysilane; NMP: Nitroxide-Mediated Polymerization; ORMOCERs: Organically Modified Ceramics; ORMOSILs: Organically Modified Silica; OTES: Octyltriethoxysilane; OTMS: Octadecyltrimethoxysilane; PAA: Poly(acrylic acid); PDMS: Polydimethylsiloxane; PEO-PPO-PEO: Poly (ethylene oxides)-b-poly (propylene oxides)-b-poly (ethylene oxides); PHPS: Perhydropolysilazane; PMMA: Poly(methyl methacrylate); POSS: Polyhedral Oligomeric Silsesquioxane; PTMO: Poly(tetramethylene oxide); PTMS: Phenyltrimethoxysilane; PTMS: Phenyltrimethoxysilane; PVP: Poly (vinylpyrrolidone); RAFT: Reversible addition- fragmentation chain transfer; Si: Silicon; Sn: Tin; Ta: Tantalum; TBN: 4-(triethoxysilyl)butyronitrile; TEM: Transmission Electron Microscopy; TEMED: N,N,N′,N′-tetramethylethylenediamine; TEOS: Tetraethoxysilane; Tg: Glass-Transition Temperature; THF: Tetrahydrofuran; Ti: Titanium; TMOS: Tetramethoxysilane; UV: Ultraviolet; VTES: Vinyltriethoxysilane; VTMS: Vinyltrimethoxysilane; Zr: Zirconium
- Highlights
Advantages of hybrid systems over the conventional materials
Discusses the fundamental aspects of sol-gel chemistry
Focusses on a detailed classification of hybrid polymers
Covers different synthetic strategies, properties, and applications in diverse fields
998.
A new cyano-bridged GadoliniumⅢ-IronⅢ complex {[Gd(DMF)3(DMSO)(H2O)3](μ-CN)[Fe(CN)5]}·2H2O (DMF=N,N-dimethylformamide; DMSO=dimethylsulfoxide) was synthesized by the grinding reaction method. It crysta-llizes in the triclinic, space group P1 with cell parameters: a=0.90363(2) nm, b=1.250 78(3) nm, c=1.41303(1) nm, α=93.174(1)°, β=94.406(1)°, γ=91.817(2)°, and V=1.588 87(5) nm3, Dc=1.582 g·cm-3, Z=2, Mr=756.72, F(000)=760, μ=2.645 mm-1. The slightly distorted square-antiprism eightfold-coordinated Gd(Ⅲ) and the approxi-mately oriented octahedrally sixfold-coordinated Fe(Ⅲ) are linked by a cyano-bridge group to construct a dinuclear compound. The {[Gd(DMF)3(DMSO)(H2O)3](μ-CN)[Fe(CN)5]} species are held together via hydrogen bonds to form a three-dimensional framework. The Gd(Ⅲ)-Fe(Ⅲ) interaction is antiferromagnetic. CCDC: 223430. 相似文献
999.
A polyoxometalate‐based inorganic–organic hybrid compound [CoII(2, 2′‐bpy)2]2[Mo8O26] ( 1 ) was synthesized by hydrothermal methods and structurally characterized by IR spectrum, TG analysis and X‐ray diffraction. The compound crystallizes in the monoclinic system, space group P21/n, a = 10.0681(2), b = 16.4467(2), c = 15.7838(3) Å, β = 100.046(1)°, V = 2573.52(8) Å3, Z = 2. The structure of 1 is built up from β‐[Mo8O26]4? subunits covalently linked via [CoII(2, 2′‐bpy)2]2+ fragments into a infinite 1D {[CoII(2, 2′‐bpy)2]2[Mo8O26]}∞ polymer. 相似文献
1000.