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81.
Amorphous electrolytes consisting of the lithium salts, Li[R-NSO2CF3] were prepared and the attendant low ionic conductivities of the lithium salt mixtures (1×10−6 S cm−1 at room temperature) are attributed to high glass transition temperatures. An example is the novel amorphous salt, Li[18-C-6NSO2CF3] which produces an amorphous salt mixture with Li[N(SO2CF3)2] (LiTFSI). 相似文献
82.
Alice J. Boyall Keith B. Dillon Philippa K. Monks Jennifer C. Potts 《Heteroatom Chemistry》2007,18(6):609-612
The di‐ium dication formed by triflic acid protonation of the cyclic triphosphenium ion derived from 1,4‐bis‐diphenylphosphinobutane, (dppb), and P3(X = Br or Cl) decomposes via an acyclic dication bearing a PHX group; this intermediate is reduced by SnX2 in the presence of HX to yield a dication with a PH2 primary phosphane terminal group, which is comparatively stable. The structure of this species has been unequivocally confirmed by 31P solution‐state NMR spectroscopy. © 2007 Wiley Periodicals, Inc. Heteroatom Chem 18:609–612, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20302 相似文献
83.
Materials with the LiAlF4 composition are of interest as protective electrode coatings in Li ion battery applications due to their high cationic conductivity. Here classical molecular dynamics calculations are used to produce amorphous model structures by simulating a quench from the molten state. These are analysed in terms of their individual pair correlation functions and atomic coordination environments. This indicates that amorphous LiAlF4 is formed of a network of corner sharing AlF6 octahedra. Li ions are distributed within this network, primarily associated with non-bridging fluorine atoms. The nature of the octahedral network is further analysed through intra‐ and interpolyhedral bond angle distributions and the relative populations of bridging and non-bridging fluorine ions are calculated. Network topology is considered through the use of ring statistics, which indicates that, although topologically well connected, LiAlF4 contains an appreciable number of corner‐linked branch‐like AlF6 chains. Thermal expansion values are determined above and below the predicted glass transition temperature of 1340 K. Finally, movement of Li ions within the network is examined with predictions of the mean squared displacements, diffusion coefficients and Li ion activation energy. Different regimes for lithium ion movement are identified, with both diffusive and sessile Li ions observed. For migrating ions, a typical trajectory is illustrated and discussed in terms of a hopping mechanism for Li transport. 相似文献
84.
Silver(I) and copper(I) are known to form reversible complexes with π bonds, which have been exploited in LC for separating unsaturated organic compounds. Prominent examples include the use of AgNO3‐impregnated silica gel in LC, and the use of copper(I) salts for selective extraction of alkenes from hydrocarbon mixtures. The Dewar–Chatt–Duncanson model is often invoked to explain the interaction between Ag(I) and Cu(I) and π bonds. However, it is unclear if such a reversible interaction is directly related to their d10 outer electronic configurations. Particularly, Au(I) has not been reported to separate olefins with different numbers of double bonds in LC. Also, there has not been a systematic comparison of the liquid chromatographic properties of other d10 transition metal salts (e.g., Zn(II), Cd(II)), making it difficult to fully understand the observed reversible interactions of Ag(I) and Cu(I) with π bonds. We demonstrate for the first time that silica gel impregnated with all three Group 11 transition metals with 1+ oxidation state strongly and similarly retain olefin compounds in LC, while transition metals from Groups 10 and 12 do not. We also tested a range of functionalized silica gels to improve the stability of Cu(I) and Au(I) ions on the surface of the silica. 相似文献
85.
J. B. Brown J. Frankel A. Rollett F. C. Whitmore H. M. Crooks Jr A. A. Pantsios W. F. Whitmore A. I. Gebhart N. Bunzelman R. Witenberg G. Petrow Ja. Schmidt C. P. A. Kappelmeier A. Kraus A. Ruff A. Krynicki D. D. van Slyke R. T. Dillon G. Denigès H. R. Snyder R. H. Levin P. F. Wiley und D. St. Tarbell 《Fresenius' Journal of Analytical Chemistry》1943,125(5-6):204-212
Ohne Zusammenfassung 相似文献
86.
Matthew G. Davidson Keith B. Dillon Judith A.K. Howard Sarah Lamb Mark D. Roden 《Journal of organometallic chemistry》1998,550(1-2)
The synthesis of a bulky secondary phosphine, Ar2PH [Ar=C6H2(CF3)3-2,4,6], and its use in the first synthesis and isolation of a phosphonium phosphide, (Ph3PMe)+(Ar2P)−, via the deprotonation of Ar2PH with a nonstabilised phosphorus ylide, Ph3P=CH2, are reported. An X-ray structure of this salt reveals that cations and anions are weakly associated in the solid state through C–HP interactions. 相似文献
87.
应用新发展的单一轨迹积分方法求解库仑加线性位的基态量子波函数,得到基态能量和波函数的一般解析表达式,并讨论了解的收敛性.应用此方法讨论了重夸克偶素系统. 相似文献
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