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U. Gelius S. Svensson H. Siegbahn E. Basilier Å. Faxälv K. Siegbahn 《Chemical physics letters》1974,28(1):1-7
The line profile of the narrow, symmetric 1s line from neon, recorded with the new ESCA instrument with X-ray monochromatization, is analyzed. The natural linewidth of this line is found to be 0.23 ± 0.02 eV, in good agreement with theoretical calculations of the oscillator strengths for Auger transitions and X-ray emission. Spectra from molecules show frequently asymmetric core electron lines under high resolution. This rules out previous explanations based on a chemical influence on the natural lifetime. Contrary to earlier assumptions, vibrational excitations are shown to be important in core electron spectra. For methane, the vibrational energy spacing is large enough to allow the vibrational lines to be partly resolved. Recent results from accurate PNO CI calculations on methane agree well with the experimental findings. The Franck-Condon transitions in the C1s and N1s lines from CO and N2 are shown to be well described in the harmonic approximation and approximating the potential curves of the highly excited core hole states with the potential curve for the ground state of NO+, X1 Σ+. Knowledge of vibrational excitations in core electron spectra is shown to be valuable in the analysis of high resolution X-ray emission spectra of free molecules. 相似文献
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O.?Docenko M.?Tamanis R.?FerberEmail author A.?Pashov H.?Kn?ckel E.?Tiemann 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2005,36(1):49-55
We present a detailed experimental study of the D1Π state of the
NaRb molecule by means of Fourier transform spectroscopy of laser induced
fluorescence. The entire data field for the D1Π state of Na85Rb
and Na87Rb consists of rovibrational levels with v′=0-39 and
J′=1-200. The data were incorporated into a direct fit of a
single potential energy curve to the level energies using the Inverted
Perturbation Approach method. The D1Π state q factors, which
describe the Λ-doubling, have been obtained in a wide range of
rotational and vibrational quantum numbers. Analysis revealed several
perturbation regions in the D1Π state.
Electronic supplementary material Online Material 相似文献
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V. N.?KuzovkovEmail author W.?von Niessen 《The European Physical Journal B - Condensed Matter and Complex Systems》2004,42(4):529-542
The method proposed by the present authors to deal analytically
with the problem of Anderson localization via disorder [J. Phys.:
Condens. Matter 14, 13777 (2002)] is generalized for higher
spatial dimensions D. In this way the generalized Lyapunov
exponents for diagonal correlators of the wave function,
2n,m , can be calculated analytically and
exactly. This permits to determine the phase diagram of the
system. For all dimensions D > 2 one finds intervals in the
energy and the disorder where extended and localized states
coexist: the metal-insulator transition should thus be interpreted
as a first-order transition. The qualitative differences permit to
group the systems into two classes: low-dimensional systems
(2D 3), where localized states are always
exponentially localized and high-dimensional systems (D
Dc=4), where states with non-exponential localization are also
formed. The value of the upper critical dimension is found to be
D0=6 for the Anderson localization problem; this value is also
characteristic of a related problem – percolation. 相似文献
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K.?Pajuste M.?Gosteva D.?Kaldre M.?Plotniece B.?Cekavicus A.?Sobolev A.?Priksane G.?Tirzitis G.?Duburs A.?PlotnieceEmail author 《Chemistry of Heterocyclic Compounds》2011,47(5):597-601
The effect of the solvent nature and temperature on the quaternization of 3,5-diethoxycarbonyl-2,6-di- methyl-4-(3-pyridyl)-1,4-dihydropyridine
by lipophilic alkyl bromides has been investigated. By comparison of the solvent effect (acetone, acetonitrile, and 2-butanone)
on the alkylation of the pyridine fragment of 3,5-diethoxycarbonyl-2,6-dimethyl-4-(3-pyridyl)-1,4-dihydropyridine it was established
that conducting the reaction in acetonitrile at 81 °C is the most optimal. 相似文献
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We show that for any open convex polygon P, there is a constant k(P) such that any k(P)-fold covering of the plane with translates of P can be decomposed into two coverings. 相似文献
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Dániel Gerbner Balázs Keszegh Nathan Lemons Cory Palmer Dömötör Pálvölgyi Balázs Patkós 《Graphs and Combinatorics》2013,29(5):1355-1364
A family ${\mathcal{F} \subseteq 2^{[n]}}$ saturates the monotone decreasing property ${\mathcal{P}}$ if ${\mathcal{F}}$ satisfies ${\mathcal{P}}$ and one cannot add any set to ${\mathcal{F}}$ such that property ${\mathcal{P}}$ is still satisfied by the resulting family. We address the problem of finding the minimum size of a family saturating the k-Sperner property and the minimum size of a family that saturates the Sperner property and that consists only of l-sets and (l + 1)-sets. 相似文献