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351.
Kaoru Yamanouchi Takahiro Matsuzawa Kozo Kuchitsu Yoshiaki Hamada Masamichi Tsuboi 《Journal of Molecular Structure》1985
The quadratic force constants of the five possible conformers of allylamine were calculated by an ab initio MC method. The infrared spectra of this molecule in the gas phase were remeasured and analyzed on the basis of the calculated vibrational frequencies. A potential energy surface with respect to the skeletal torsions was also calculated. The relative abundances of the S+G+, ST, CT, CG, and S+G? conformers, predicted to be 44:32:16:7:1 at room temperature, are consistent with the experimental data. 相似文献
352.
Takashi Nagata Mutsumi Suzuki Kaoru Suzuki Tamotsu Kondow Kozo Kuchitsu 《Chemical physics》1984,88(1):163-170
Unequal intensities of the Λ-doublet components were observed in the CH(A2Δ-X2Π) emission following the multiphoton dissociation of (CH3)2CO, (CH3)2S and CH3NO2 by an ArF laser (193 nm). The power dependence of the emission intensity was estimated to be cubic (3.1±0.2) when the laser power was below ≈ 8×1017 photons cm?2 pulse?1. The Λ-doublet populations depended on the rotational quantum number N′ and the preferred level changed at N′ = 20. A similar behavior was observed for the CD(A2Δ) from (CD3)2CO. Rotational distributions show bimodal behavior, having a hump around N′ = 13 in CH(A2Δ) and N′ = 11 in CD(A2Δ). These trends indicate that the CH(A2Δ) is produced through multiple processes where stepwise mechanisms are operative via either CH2 or CH3, or both radicals as intermediates. 相似文献
353.
A new Monte Carlo technique is applied to solve difference equations of elliptic and parabolic partial differential equations with given boundary values. Fixed random walk is extended to modified random walk, whereby a random walk is made on a maximum square. The average number of steps and the computational time in a modified random walk is much less than in a fixed random walk. Numerical examples support the utility of this method. 相似文献
354.
355.
356.
-Benzylidene--2,4,6-tri--butylphenylphosphine containing phosphorus in low coordination state was irradiated to give the corresponding -isomer: both isomers were isolated and characterized and the reactions with chromium(O) carbonyls were described. 相似文献
357.
A high-resolution infrared spectrum of methane-d2 has been measured in the C-D stretching band region (2025–2435 cm?1). Rotational structures of the ν2 and ν8 bands have been assigned by use of the ASSIGN-diagram method, and the c-type Coriolis interaction between ν2 and ν8 has been analyzed. The band origins, ν2 = 2203.22 ± 0.01 cm?1 and ν8 = 2234.70 ± 0.01 cm?1, the rotational constants and the centrifugal distortion constants for the two bands, and the Coriolis coupling constant, , have been determined. 相似文献
358.
Masashi Uematsu Hisato Hiraishi Tsutomu Fukuyama Tamotsu Kondow Kozo Kuchitsu 《Chemical physics》1982,64(3):381-387
When benzene, acetylene and ethylene were allowed to collide with Ne Rydberg atoms (17?n?40), significant Ne+ ions were observed. Their cross sections were estimated, with reference to the ionization by H2O, to be as large as 10?14–10?15 cm2. However, no Ne+ signals were observed when ethane, methane and N2 were used as targets. Theoretical estimates of the cross sections for ionization by interaction of the quadrupole moment and polarizability of the first three molecules are several orders of magnitude smaller than the experimental cross sections given above. A similarity of this phenomenon to the scattering of a thermal electron by benzene etc., observed by Christophorou et al., is suggested. 相似文献
359.
Kaoru Yamanouchi Hajime Watanabe Seiichiro Koda Soji Tsuchiya Kozo Kuchitsu 《Chemical physics letters》1984,107(3):290-294
Laser-induced fluorescence spectra of Ne- and Ar -aniline complexes were observed with a resolution of 0.04 cm?1. By a simulation analysis of the rotational structures, the distances between the rare-gas atom and the aromatic ring of aniline were found to be 3.35 ± 0.04 and 3.50 ± 0.04 A in the X?1A1 state of the Ne and Ar complexes, respectively, and about 0.05 A shorter when aniline was excited to the Ã1B2 state. 相似文献
360.