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51.
Dr. Yinhua Huang Guo Hao Chan Prof. Shunsuke Chiba 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(23):6644-6647
A new protocol for amide-directed ortho and lateral C−H sodiation is enabled by sodium hydride (NaH) in the presence of either sodium iodide (NaI) or lithium iodide (LiI). The transient organosodium intermediates could be transformed into functionalized aromatic compounds. 相似文献
52.
Back Cover: Understanding the Origins of Nucleophilic Hydride Reactivity of a Sodium Hydride–Iodide Composite (Chem. Eur. J. 21/2016)
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53.
Jensen P Odaka TE Kraemer WP Hirano T Bunker PR 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2002,58(4):763-794
We have developed a computational procedure, based on the variational method, for the calculation of the rovibronic energies of a triatomic molecule in an electronic state that become degenerate at the linear nuclear configuration. In such an electronic state the coupling caused by the electronic orbital angular momentum is very significant and it is called the Renner effect. We include it, and the effect of spin-orbit coupling, in our program. We have developed the procedure to the point where spectral line intensities can be calculated so that absorption and emission spectra can be simulated. In order to gain insight into the nature of the eigenfunctions, we have introduced and calculated the overall bending probability density function f(p) of the states. By projecting the eigenfunctions onto the Born-Oppenheimer basis, we have determined the probability density functions f+(rho) and f-(rho) associated with the individual Born-Oppenheimer states phi(-)elec and phi(+)elec. At a given temperature the Boltzmann averaged value of the f(p) over all the eigenstates gives the bending probability distribution function F(rho), and this can be related to the result of a Coulomb Explosion Imaging (CEI) experiment. We review our work and apply it to the molecules CH2+, MgNC and NH2, all of which are of astrophysical interest. 相似文献
54.
Muramatsu Y Ueda K Saito N Chiba H Lavollée M Czasch A Weber T Jagutzki O Schmidt-Böcking H Moshammer R Becker U Kubozuka K Koyano I 《Physical review letters》2002,88(13):133002
The doubly degenerate core-excited Pi state of CO2 splits into two due to static Renner-Teller effect. Using the triple-ion-coincidence momentum imaging technique and focusing on the dependence of the measured quantities on the polarization of the incident light, we have probed, directly and separately, the linear and bent geometries for the B1 and A1 Renner-Teller pair states, as a direct proof of the static Renner-Teller effect. 相似文献
55.
It is shown that a square invariant of the Weyl conformal curvature tensor can lead to a Lagrangian in a variational principle for a gravitational equation in vacuum of the Bianchi identity type which is compatible with the Einstein equation. Moreover we show that such a Lagrangian implicitly includes a conformally invariant theory characterized by two gauge fields and the metric tensor. 相似文献
56.
The refractive index of SiO2-P2O5 glass prepared by a modified chemical vapor deposition method is measured using an interference microscope. It is found that the refractive index in bulk form increases linearly at 9.5×10-4 (mol.%)-1 as the P2O5 concentration increases. It is also found that quenching at extremely high speed reduces the refractive index over 2 mol.% P2O5. The wavelength dispersion of the refractive index dn/dλ is constant up to 5 mol.% P2O5 producing a refractive index difference of 5×10-3 compared with fused silica. Consequently, this glass materials is thought to be suitable for wide band-width optical fiber applications. 相似文献
57.
The electronic absorption spectra of four monosubstituted naphthalenes, α-, β-naphthols, and α-, β-naphthylamines have been investigated by means of configuration analysis with particular attention to the dependence of spectra on the position of substitution and on the electron-donating power of the substituent. The results of molecular orbital calculations based on the Pariser-Parr-Pople method are analyzed in terms of locally excited states and intramolecular charge-transfer configurations. The characteristic changes in location and polarization of the Lb, La, and Bb bands caused by substitution at the α- or β-position are adequately explained by the analysis. Two strong absorption bands of α-substituted naphthalenes, which appear in place of the Bb band of naphthalene, are shown to result from a mixing of the and states. The amino group exerts a great influence on the electronic structure of the parent molecule, so that the Bb band cannot be identified in the spectrum of β-naphthylamine. 相似文献
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Tsuneo Uematsu 《Zeitschrift fur Physik C Particles and Fields》1985,29(1):143-146
We discuss a component formalism ofN=1 supergravity theories in 2 and 3 spacetime dimensions. Starting from gauge theories of the superconformal group, we derive the tensor calculus for conformal and Poincaré supergravity theories. A supersymmetric extension of the non-trivial analog of Einstein's equation for 2 dimensions is given in terms of the scalar curvature multiplet. 相似文献