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101.
Sekiguchi A Ishida Y Fukaya N Ichinohe M Takagi N Nagase S 《Journal of the American Chemical Society》2002,124(7):1158-1159
Dark red crystals of the halogen-substituted cyclotrigermenes [(tBu3Si)3Ge3X; X = Cl, Br, I] were obtained in good yields by the reaction of [(tBu3Si)3Ge3]+.TTFPB- (TTFPB- = tetrakis(2,3,5,6-tetrafluorophenyl)borate) with potassium halides (KCl, KBr, or KI) in diethyl ether. The crystal structures of the halogen-substituted cyclotrigermenes reveal a cis-bent Ge=Ge double bond, caused by the introduction of the electronegative halogen atom on the sp3 germanium atom of cyclotrigermene. In solution, an intramolecular halogen migration over the three-membered ring skeleton was observed. Facial stereoselectivity in the Diels-Alder reaction of new cyclotrigermenes with 2,3-dimethyl-1,3-butadiene is also reported. 相似文献
102.
103.
Munetaka Nakata Masaaki Sugie Harutoshi Takeo Chi Matsumura Tsutomu Fukuyama Kozo Kuchitsu 《Journal of Molecular Spectroscopy》1981,86(1):241-249
The microwave spectra of four isotopic species of dichlorine monoxide (OCl2) have been observed, and the rotational constants have been obtained. The rm structure for each isotopic species has been determined by Watson's method. The equilibrium structure has been estimated by taking proper averages of rm structures to be and ∠eClOCl = 110.886(6)°. The general applicability and the merit of the present method for estimating the equilibrium structure are pointed out. 相似文献
104.
105.
106.
Masaaki Yamagishi 《Journal of Quantitative Spectroscopy & Radiative Transfer》1976,16(6):543-548
Measurements of relative intensities of spectral lines and of plasma parameters have been carried out in an Ar-O2 d.c. glow discharge under the following conditions: gas pressures of 1, 2 and 3 torr and partial pressures for O2 of 0, 0.01, 0.02, 0.05 and 0.1 torr. Many of the Ar line intensities decreased when O2 was added, while some were enhanced. Enhancement of the 6677A and 7504A lines has been most notable. The number density of metastable Ar atoms is decreased when O2 is added. Upon addition of O2, the electron temperature is decreased and the electron density increased, except at a gas pressure of 1 torr; the electric field strength in the positive column is also increased. 相似文献
107.
The degeneracy in the Heisenberg model of the three chromium clusters having D3 symmetry is split by the antisymmetric exchange interaction. Based on this new energy level scheme, the low temperature behavior of the specific heat and magnetic susceptibility are reexamined. 相似文献
108.
Masaaki Ito 《Physics letters. A》1984,104(5):248-250
A recursion operator for the classical Boussinesq equation is given, which yields infinitely many symmetries and conservation laws. It is also shown that these symmetries define a hierarchy of the classical Boussinesq equation each of which is a hamiltonian system. 相似文献
109.
Hamao Watanabe Kazuaki Higuchi Tomoko Goto Tsutomu Muraoka Jun Inose Masaaki Kageyama Yasuko Iizuka Masakatsu Nozaki Yoichiro Nagai 《Journal of organometallic chemistry》1981,218(1):27-39
In the presence of a catalytic amount of sodium methoxide, sym-dimethoxytetramethyldisilane was converted into α,ω-dimethoxypermethylpolysilanes, MeO(SiMe2)nOMe where n ? 3, at room temperature. On the other hand, similar treatment of the disilane in THF solution gave cyclic polysilanes, (Me2Si)n where n = 5–7. Decomposition of the disilane in the presence of diphenylacetylene afforded a trisilacyclopentene derivative under similar conditions. This compound was obtained also by the reaction between α,ω-dimethoxypermethylpolysilanes and diphenylacetylene in the presence of sodium methoxide. These cyclic products most likely were formed via permethyl polysilyl anion intermediates derived from α,ω-dimethoxypermethylpolysilanes. Also, the formation of α,ω-dimethoxypermethylpolysilanes could be elucidated in terms of the mechanism involving the base-assisted, concerted nucleophilic substitution or stepwise substitution by silyl anions, rather than the successive dimethylsilylene (Me2Si:) insertion reaction. 相似文献
110.