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881.
Photodetachment of AgX(-) (X = Cl, Br, I) and AuCl(-) is studied by a photoelectron velocity map imaging technique and theoretical calculations. Photoelectron spectra (PES) and photoelectron angular distributions (PADs) were obtained. The vibrationally resolved spectra provided approximately equal electron affinities (EAs) for AgX: 1.593(22) eV for AgCl, 1.623(21) eV for AgBr, and 1.603(22) eV for AgI, respectively. Franck-Condon simulations of these spectra gave the equilibrium bond lengths and vibrational frequencies of the title anions. Relativistic density functional theory (DFT) calculations using BLYP, PW91, PBE, and BP86 functionals have been performed to predict the EAs of the AgX (X = Cl, Br, I) molecules. The computed EAs at the BP86 level of theory are in good agreement with the experimental values. Energy partitioning analyses (EPA) at the BP86(ZORA)/QZ4P level of theory of both anions and their neutrals were reported. 相似文献
882.
Pd/PtBu(3)-catalyzed intramolecular C-O bond formation has been used to access aryl- and alkyl-substituted benzoxazinones. 相似文献
883.
Gao K Yu CB Li W Zhou YG Zhang X 《Chemical communications (Cambridge, England)》2011,47(27):7845-7847
Highly enantioselective hydrogenation of seven-membered cyclic imines, substituted dibenzo[b,f][1,4]oxazepines, was achieved, with up to 94% ee, by using the [Ir(COD)Cl](2)/(S)-Xyl-C(3)*-TunePhos complex as the catalyst in the presence of morpholine-HCl. 相似文献
884.
(S(p))-(+)-Spiniferin-1 and (R(p))-(-)-spiniferin-1, a pair of unusual marine natural products with planar chirality, were firstly synthesized via a polyfluoroalkanosulfonyl fluoride induced homoallylic carbocation rearrangement reaction. The chiral resolution and palladium-catalyzed β-H elimination of allylic alcohol derivatives were considered as the key steps of these divergent syntheses. 相似文献
885.
Ding T Tian Y Liang K Clays K Song K Yang G Tung CH 《Chemical communications (Cambridge, England)》2011,47(8):2429-2431
Oxygen plasma etching of electrospun polymer fibers containing spherical colloids is presented as a new approach towards anisotropic colloidal nanoparticles. The detailed morphology of the resulting nanoparticles can be precisely controlled in a continuous way. The same approach is also amenable to prepare inorganic nanoparticles with double-sided patches. 相似文献
886.
Ge HM Yan W Guo ZK Luo Q Feng R Zang le Y Shen Y Jiao RH Xu Q Tan RX 《Chemical communications (Cambridge, England)》2011,47(8):2321-2323
Precursor-fed cultivation of endophytic Chaetomium globosum 1C51 afforded nine novel "unnatural" halogenated chaetoglobosins including those with more preferable immunosuppressive activity. 相似文献
887.
Thermal behavior of 1,2,3-triazole nitrate 总被引:1,自引:0,他引:1
Liang Xue Feng-Qi Zhao Xiao-Ling Xing Zhi-Ming Zhou Kai Wang Hong-Xu Gao Jian-Hua Yi Si-Yu Xu Rong-Zu Hu 《Journal of Thermal Analysis and Calorimetry》2011,104(3):999-1004
The thermal decomposition behaviors of 1,2,3-triazole nitrate were studied using a Calvet Microcalorimeter at four different
heating rates. Its apparent activation energy and pre-exponential factor of exothermic decomposition reaction are 133.77 kJ mol−1 and 1014.58 s−1, respectively. The critical temperature of thermal explosion is 374.97 K. The entropy of activation (ΔS
≠), the enthalpy of activation (ΔH
≠), and the free energy of activation (ΔG
≠) of the decomposition reaction are 23.88 J mol−1 K−1, 130.62 kJ mol−1, and 121.55 kJ mol−1, respectively. The self-accelerating decomposition temperature (T
SADT) is 368.65 K. The specific heat capacity was determined by a Micro-DSC method and a theoretical calculation method. Specific
heat capacity equation is
C\textp ( \textJ mol - 1 \text K - 1 ) = - 42.6218 + 0.6807T C_{\text{p}} \left( {{\text{J mol}}^{ - 1} {\text{ K}}^{ - 1} } \right) = - 42.6218 + 0.6807T (283.1 K < T < 353.2 K). The adiabatic time-to-explosion is calculated to be a certain value between 98.82 and 100.00 s. The critical
temperature of hot-spot initiation is 637.14 K, and the characteristic drop height of impact sensitivity (H
50) is 9.16 cm. 相似文献
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