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排序方式: 共有117条查询结果,搜索用时 140 毫秒
1.
Marty W. DeGroot Chhatra Khadka Harald Rösner John F. Corrigan 《Journal of Cluster Science》2006,17(1):97-110
The thermolysis of the zinc trimethylsilylchalcogenolate complexes (N,N′-tmeda)Zn(ESiMe3)2 (E = S, 1; E = Se, 2) and (3,5-Me2-C5H3N)2Zn(ESiMe3)2 (E = S, 3; E = Se, 4) has been investigated. Solid-state thermal decomposition of complexes 1–4 above 250°C results in the formation of hexagonal ZnS and cubic ZnSe, respectively, via the liberation of TMEDA (1–2) or 3,5-lutidine (3–4) and E(SiMe3)2. Solid-state or solution thermolysis of these complexes up to 200°C produces nanocrystalline ZnS and ZnSe materials whose surface is protected by either coordinated TMEDA or 3,5-lutidine ligands. The progress of the step-wise solid-state decomposition of these complexes was monitored by thermogravimetric and single differential thermal analysis and volatile decomposition products in both solution and solid-state experiments were identified by GC/MS.Dedicated to Professor Brian F. G. Johnson on the occasion of his retirement. 相似文献
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Reactions of CuCl with Te(Ph)SiMe3 and solublizing trialkylphosphine ligands afford a series of polynuclear copper-phenyltellurolate complexes that has been structurally characterized. The formation of the complexes is found to be highly dependent on the ancillary phosphine ligand used. The synthesis and structures of [Cu2(mu-TePh)2(PMe3)4] 1, [Cu4(mu3-TePh)4(PPr(i)3)3] 2, [Cu5(mu-TePh)3(mu3-TePh)3(PEt3)3][PEt3Ph] 3, and [Cu12Te3(mu3-TePh)6(PEt3)6] 4 are described. The telluride (Te(2-)) ligands in 4 arise from the generation of TePh2 in the reaction mixtures. The subsequent co-condensation of clusters 3 and 4 leads to the generation of the nanometer sized complex [Cu29Te9(mu3-TePh)10(mu4-TePh)2(PEt3)8][PEt3Ph] 5 in good yield, in addition to small amounts of [Cu39(mu3-TePh)10(mu4-TePh)Te16(PEt3)13] 6. These complexes are formed via the photo elimination of TePh2. The cyclic voltammogram of 5 in THF solution exhibits two oxidation waves, assigned to the oxidation of the Cu(I) centers. 相似文献
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The copper-tellurolate cluster [(Cu(6)(TePh)(6)(PPh(2)Et)(5)] has been loaded into the pores of MCM-41 by solid-state impregnation techniques. It was found that the best loading conditions are 110 degrees C and 10(-)(3) Torr static vacuum. The resulting material was analyzed by powder X-ray diffraction (PXRD), nitrogen adsorption isotherms, thermogravimetric analysis (TGA), (31)P CP MAS NMR spectroscopy, and TEM. It was observed that loading is accompanied by loss of the phosphine shell, with retention of the copper-tellurium core. Condensation of the impregnated material may proceed thermally or photochemically. Thermal condensation results in the formation of Cu(2)Te nanoparticles as demonstrated by PXRD, and TEM data suggests that the process has taken place inside the pores of MCM-41. Photochemical condensation yields larger metal-chalcogen clusters in the pores as suggested by the result of UV-vis diffuse reflectance spectroscopy and TEM measurements. 相似文献
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Back Cover: New Polydentate Trimethylsilyl Chalcogenide Reagents for the Assembly of Polyferrocenyl Architectures (Chem. Eur. J. 23/2014)
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7.
New Polydentate Trimethylsilyl Chalcogenide Reagents for the Assembly of Polyferrocenyl Architectures
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Mahmood Azizpoor Fard Bahareh Khalili Najafabadi Mahdi Hesari Prof. Dr. Mark S. Workentin Prof. Dr. John F. Corrigan 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(23):7037-7047
A series of polychalcogenotrimethylsilane complexes Ar(CH2ESiMe3)n, (Ar=aryl; E=S, Se; n=2, 3, and 4) can be prepared from the corresponding polyorganobromide and M[ESiMe3] (M=Na, Li). These represent the first examples of the incorporation of such a large number of reactive ?ESiMe3 moieties onto an organic molecular framework. They are shown to be convenient reagents for the preparation of the polyferrocenylseleno‐ and thioesters from ferrocenoyl chloride. The synthesis, structures, and spectroscopic properties of the new silyl chalcogen complexes 1,4‐(Me3SiECH2)2(C6Me4) (E=S, 1 ; E=Se, 2 ), 1,3,5‐(Me3SiECH2)3(C6Me3) (E=S, 3 ; E=Se, 4 ) and 1,2,4,5‐(Me3SiECH2)4(C6H2) (E=S, 5 ; E=Se, 6 ) and the polyferrocenyl chalcogenoesters [1,4‐{FcC(O)ECH2}2(C6Me4)] (E=S, 7 ; E=Se, 8 ), [1,3,5‐{FcC(O)ECH2}3(C6Me3)] (E=S, 9 ; E=Se, 10 ) and [1,2,4,5‐{FcC(O)ECH2}4(C6H2)] (E=S, 11 illustrated; E=Se, 12 ) are reported. The new polysilylated reagents and polyferrocenyl chalcogenoesters have been characterized by multinuclear NMR spectroscopy (1H, 13C, 77Se), electrospray ionization mass spectrometry and, for complexes 1 , 2 , 3 , 4 , 7 , 8 , and 11 , single‐crystal X‐ray diffraction. The cyclic voltammograms of complexes 7 – 11 are presented. 相似文献
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The widespread use of point of care testing in biomedical and clinical applications is a major aim of the electrochemical field. A large number of groups are working on lab-on-a-chip systems or sensor arrays which are underpinned by electrochemical detection methodologies. Miniaturized transducers have the potential to be adopted in such systems for diagnosis of a range of diseases in both clinical and nonclinical settings. In this review, we will present the current trends and state of the art for a selection of miniaturized sensing elements (microelectrodes, nanoelectrodes, and field-effect transistors) and provide an impression of current technologies, their associated performance characteristics, and also considering the major barriers to adoption and how they might be surmounted in future so these technologies can fulfil their early promise. 相似文献
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We consider the possibility of satisfying the gauge field equations in dimensions greater than four by imposing linear relations amongst the components of the field strength tensor, Fμν, generalising the idea of self-duality in four dimensions. 相似文献