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MO-theory suggests 3 as a likely candidate for a newly designed conception to replace a given redox potential by a lower one with the aid of light.  相似文献   
74.
Based on the Bohr–Sommerfeld model, we investigate the quantization of magnetic flux through the electronic orbits together with its dependence on additional sources of magnetic fields. The additional magnetic field causes changes of the angular momentum and hence shifts of the energy of the atomic levels. We study this effect for the cases of the Zeeman effect, where the source is an external homogeneous magnetic field, and the hyperfine interaction, where the source is the field of the magnetic moment of the nucleus. We discuss a model for the handling of the different angular momentum contributions for which the energy shifts due to the Zeeman effect and the magnetic dipole contribution to the hyperfine interaction can be reproduced quite well. The meaning of “spin,” however, changes within this approach drastically. The unusual Landé g-factor of the electron is discussed to be the result of a reduced ground-state angular momentum of the electron in combination with the field of the magnetic moment of the electron rather than an intrinsic property of the electron.  相似文献   
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This paper is concerned with the approximate reconstruction of the earth’s potential field from geometric and gravimetric data. This is an ill-posed problem involving typically large amounts of data which are to be continued by a harmonic function. The standard approach in geodesy is based on spherical harmonics which are globally supported. Thus, a least squares approach for the data fitting yields a linear system of equations with a fully populated system matrix. This becomes computationally prohibitive for large amounts of data and, therefore, presents the biggest bottleneck for fast and efficient computations.  相似文献   
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Surface-state-mediated interactions influence the spatial distribution of adatoms at surfaces. These indirect interactions are the driving force for the creation of superlattices of individual adsorbed atoms when the adatom concentration, the sample temperature, and the adatom diffusion barrier are in a subtle balance, as it has been first reported for Ce adatoms on Ag(1 1 1). The conditions for the formation of such superlattices are discussed. Specifically, the adatom concentration is shown to modify considerably the electronic structure of the Ag(1 1 1) surface. With increasing temperature the superlattice undergoes a direct transition from a two-dimensional solid to a two-dimensional liquid. Such superlattices, consisting of magnetic adatoms, may be interesting as model systems for the study of direct and indirect magnetic interactions in two dimensions.  相似文献   
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