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951.
The vibration-rotation spectrum of methyl isocyanide (CH3NC) has been recorded with the aid of a high-resolution Fourier transform spectrometer in the region 1370 to 1560 cm−1 containing the perpendicular band of the fundamental vibration ν6 (species E), the weaker parallel band of the ν3 (A1) fundamental, and the perpendicular combination band ν7 + ν8 (E) enhanced by Fermi resonance with ν6. Sixteen hundred seventy well-resolved lines were assigned to 15 subbands of ν6, 6 subbands of ν3, and 3 subbands of ν−7 + ν−8. A strong x, y-Coriolis resonance between ν3 and ν6 and Fermi resonance between ν±6 and the E component ν7 + ν8, as well as between ν3 and the A1,2 components ν±7 + ν8, greatly affects the spectrum. Additional weaker anharmonic interaction of ν6 with the ν4 + 2ν28 combination and higher-order rotational interactions connecting the various states were also detected in the spectrum. All of these interactions have been incorporated into a 9 × 9 Hamiltonian matrix used for modeling the upper states of the observed transitions. A set of spectroscopic constants is reported for the upper states of the bands ν3, ν6, and ν7 + ν8 and for ν4 + 2ν28 which reproduces the observed lines with an overall standard deviation of 0.0012 cm−1. 相似文献
952.
953.
Jean-Francois Le Borgne 《Journal of organometallic chemistry》1976,122(2):129-137
The condensation of metallated aldimines, prepared from activated lithium dialkylamides, with different dihalogenoalkenes gives aldehydes with a halogenovinylic group. Acidic hydrolysis of these aldehydes leads directly to cyclopentenones. When treated with an excess of activated amide, halogenovinylic aldimines give γ-acetylenic aldehydes. 相似文献
954.
955.
The electronic structure of PbMo6S8 has been investigated using the so-called EHT-tight-binding method. An idealized cubic and an experimental distorted geometry are used, with standard atomic orbital parameters and diagonal H-matrix elements. A full band structure is presented in the idealized case. In both cases, the density of state curves computed using an integration over the Brillouin zone are also presented. The results show the importance of the twisting angle on the electronic structure near the Fermi level. 相似文献
956.
A new method for the determination of the compound nucleus coherence width at high excitation energy
N. Alamanos C. Levi C. Le Metayer W. Mittig L. Papineau 《Physics letters. [Part B]》1985,151(2):100-104
The coherence width of the compound nucleus can be obtained from cross correlations of the energy spectra taken at different energies instead of the correlation function of the excitation function. In this way it is sufficient to cover an incident energy interval of the order of the compound nucleus width. We have applied this method to the reaction 12C + 28Si. The coherence width of 40Ca is found in reasonable agreement with previous determinations. Indication is obtained for the presence of a second (smaller) coherence width which could correspond to anomalous long-living compound nucleus states. 相似文献
957.
958.
Frederic Y. M. Wan 《Studies in Applied Mathematics》1977,56(3):219-239
Simple but accurate approximate solutions for R. M. Solow's theory of urban land rent with congest cost of transportation are obtained by perturbation and asymptotic methods. Only the case of an absentee landlord is discussed though the techniques used can be modified in a straightforward manner to handle the more interesting (and mathematically more complicated) case of municipal ownership. Solow's model is also extended to have expenditures for housing and space as separate items in the budget equation. This extension eliminates the ambiguity in the value for the fraction of income after travel cost spent on ground rent, without affecting the structure of the mathematical problems associated with Solow's original theory. 相似文献
959.
Alain Le Mehaute 《Journal of statistical physics》1984,36(5-6):665-676
An irreversible process in fractal media involves coupling relation between the space and the time. The present note displays how the fractional derivation has to be introduced to describe this effect. As a result the law of the chemical diffusion to a fractal is given. 相似文献
960.
Infrared and Raman spectra (4000-40 cm?1 of (η6-C6H5CO2CH3)Cr(CO)2(CNCOC6H5) are recorded and interpreted with the aid of isotopic derivatives. Vibration modes and modification of the aromatic ring bonds by coordination are discussed. 相似文献