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851.
The electronic spectrum of an icosahedral quasicrystal with a central-atom decoration of the Amman-Mackay network is investigated
in the tight-binding approximation. The quasicrystal is described as a structural limit of the optimal cubic approximants
with increasing period. The electronic spectra for the first four optimal cubic approximants do not contain the hierarchical
gap structure which is typical for the Cantor set of the spectrum of a one-dimensional quasicrystal. At the same time, as
the order of the approximant increases, the spectrum becomes singular throughout the entire energy scale.
Pis’ma Zh. éksp. Teor. Fiz. 67, No. 8, 557–562 (25 April 1998)
Published in English in the original Russian journal. Edited by Steve Torstveit. 相似文献
852.
An expression for the probability of thermally activated tunneling ionization in an electric field in the presence of a magnetic
field is obtained. It is shown that the logarithm of the ionization probability is proportional to the squared electric field,
and the coefficient of proportionality decreases with increasing magnetic field.
Pis’ma Zh. éksp. Teor. Fiz. 68, No. 10, 763–767 (25 November 1998) 相似文献
853.
854.
Mass distributions of fragments in the low-energy fission of nuclei from 187Ir to 213At have been analysed. This analysis has shown that shell effects in symmetric-mode fragment mass yields from the fission of pre-actinide nuclei could be described if one assumes the existence of two strongly deformed neutron shells in the arising fragments with neutron numbers N1 ≈ 52 and N2 ≈ 68. A new method has been proposed for quantitatively describing the mass distributions of the symmetric fission mode for pre-actinides with A ≈ 180–220. 相似文献
855.
856.
857.
It is found that, in the spherical coordinate system, the fundamental solution of the Helmholtz equation in a wedge satisfies the Sommerfeld radiation conditions at infinity uniformly in angle coordinates.Deceased.Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 45, No. 9, pp. 1312–1314, September, 1993. 相似文献
858.
859.
The quantum defect orbital (QDO ) method and its relativistic (RQDO ) counterpart have been employed in this work to compute oscillator strengths for several fine-structure transitions in members of the copper isoelectronic sequence up to Z = 92. The RQDO results are found to be in quite good agreement with the best estimates derived from other sources, whenever the comparison is possible. © 1994 John Wiley & Sons, Inc. 相似文献
860.