共查询到20条相似文献,搜索用时 15 毫秒
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G. Nagarajan 《Czechoslovak Journal of Physics》1966,16(2):157-166
The Cyvin method, utilizing symmetry coordinates, has been employed here to compute the mean-square amplitude quantities, generalized mean-square amplitudes (mean-square parallel amplitudes, mean-square perpendicular amplitudes and mean cross products) and mean amplitudes of vibration for the bonded as well as non-bonded atom pairs at the temperaturesT=298°K andT=500°K for the tetrahedral tetrahalogeno complexes of zinc, cadmium, gallium, indium, thallium and arsenic. The non-linear behaviour of the mean amplitudes of vibration in terms of the electronegativities of the central atoms has been discussed, followed by a discussion on the replacement of peripheral atoms. 相似文献
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Ab initio LCAO-SCF calculations with an extended basis set are used to predict the geometry and various vibrational properties of the hydrogen bonded complex between HCN and HF. The complex is predicted to be completely linear, HF being the proton donor. The frequencies of the intermolecular vibrations are in good agreement with experiment. The intramolecular frequency shifts and absorption intensity changes are also determined. The large increase in the intensity of the HF stretching frequency in the complex is found to be due to both charge transfer and polarization forces. 相似文献
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The broad and sharp EPR signals observed in spectra of C60 and C 60 3? are summarized and proposed assignments are discussed. The sharp signals in samples of C 60 2? are reviewed. 相似文献
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F. M. Michel-Calendini 《辐射效应与固体损伤》2013,168(2):913-918
Abstract The EPR fine and hyperfine tensors of Mn and Cr ions in cubic and tetragonal BaTiO3 have been calculated according to their positions in the oxygen octaedron surroundings using the molecular MS Xα method. 相似文献
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Results of the experiments on neutron energy spectra measurements within broad energy range from 5 x 10(-7) to 2 x 10(2) MeV aboard the Mir orbital station and equivalent neutron dose estimation are presented. Four measurement techniques were used during the experiments. The shape of spectra and their absolute values are in good agreement. According to those experiments, an equivalent neutron dose depends upon effective shielding thickness and spacecraft mass. The neutron dose mentioned is comparable with that of ionizing radiation. Neutron flux levels measured aboard the Mir station have shown that a neutron spectrometer involving broad energy range will be used within the radiation monitoring systems in manned space flights. 相似文献
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采用密度泛函理论的B3LYP混合泛函和6-311G(d,p)基组,通过几何结构优化得到了阿比特龙分子的稳定构型.计算了阿比特龙分子的红外吸收光谱,并与文献数据进行比较,将2971.01、1588.31、1536.13、1450.40、1112.13和1074.44 cm~(-1)等处吸收峰指认为特征吸收峰.在优化计算的基础上,结合Multiwfn软件分析了阿比特龙分子的前线轨道成分,得出阿比特龙分子的亲核能力明显强于其亲电能力,C55、O54原子在95αHOMO中占据的权重分别为61.79%和17.05%,C=O-H部位是其亲核反应的活性中心.研究结果对阿比特龙分子的检测、活性应用等方面具有一定的理论指导意义. 相似文献
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We investigate the spectral function of a hole moving in the orbital-ordered ferromagnetic planes of LaMnO3, and show that it depends critically on the type of orbital ordering. While the hole does not couple to the spin excitations, it interacts strongly with the excitations of e(g) orbitals (orbitons), leading to a new type of quasiparticle with a dispersion on the orbiton energy scale and with strongly enhanced mass and reduced weight. Therefore we predict a large redistribution of spectral weight with respect to the bands found in local density approximation (LDA) or in LDA+U. 相似文献
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J.A. Pople 《Molecular physics》2013,111(2):175-180
The London theory of the diamagnetic susceptibility of conjugated hydrocarbons is extended in a manner which leads to detailed information about the distribution of interatomic currents induced by a general magnetic field. The method is illustrated by a calculation of the currents flowing round the two closed rings of azulene in a uniform field. This suggests that the larger current flows in the five-membered ring. 相似文献
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The electron spin resonance (e.s.r.) spectra of the anions of toluene, p-xylene and m-xylene have been studied and the proton hyperfine coupling constants determined. These are in excellent agreement with the predictions of Hückel molecular orbital theory. 相似文献
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《Nuclear Physics A》1998,632(1):39-60
The previously developed multiphonon method is applied to the study of the quadrupole vibrational motion in even-even spherical nuclei. For the first time calculations with a model Hamiltonian containing pairing and quadrupole-quadrupole interactions are performed up to four phonons. The contributions of all the parts of the Hamiltonian are analyzed and it is shown that some terms generally omitted cannot be neglected. 相似文献
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A modified Iterative Extended Hückel Method (MIEHM) is introduced and applied to the photoelectron spectra of benzene, pyridine, pyrazine, pyrimidine, pyridazine, s-triazine and s-tetrazine. Guided by comparison with available ab initio Hartree-Fock calculations, the molecular orbitals are divided into four categories. The correlation between calculated orbital energies and experimental ionization energies is then established separately for each group of orbitals, leading to a consistent interpretation of the first ten bands in the photoelectron spectra. The resulting assignment is in general agreement with the one proposed by Gleiter. Heilbronner and Hornung4 on the basis of empirical correlation procedures. 相似文献