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Heinrich R. Karfunkel Thomas Dressler Andreas Hirsch 《Journal of computer-aided molecular design》1992,6(5):521-535
Summary Substituting carbon atoms of fullerenes by heteroatoms and vacancies will lead to new and yet unknown spherical-shaped molecules termed hereafter as heterofullerenes. The enormous structural diversity of these molecules is investigated and their structural, electronic and thermochemical properties are predicted using semiempirical computations. Computational results for complexes with ions lead to the hypothesis that these molecules behave like microscopic Faraday cages in which the electrons concentrate on the outer side of the sphere. It is predicted that some of these heterofullerenes are structurally and electronically similar to phthalocyanines and related molecules but offer many additional advantages. Potential uses such as adding heterofullerenes to fullerene materials, as superior starting materials for the fabrication of diamonds, as catalysts in hydrogenation reactions, as components of materials dominated until now by phthalocyanines, etc., are discussed. Simple synthetic routes to these compounds that are based on minor alternations of existing methods for fullerene production are proposed. On the basis of the thermochemical calculations, we believe that the most promising possibility consists of using metal cyanide/graphite composite target rods instead of pure graphite rods as in a conventional fullerene synthesis. 相似文献
967.
Andreas E. Schroth 《Journal of Geometry》1994,51(1-2):138-149
The number of circles of a four-dimensional locally compact Laguerre plane touching three given circles or points depends only on the given geometric configuration but not on the Laguerre plane. 相似文献
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An interior-point affine-scaling trust-region method for semismooth equations with box constraints 总被引:1,自引:0,他引:1
An algorithm for the solution of a semismooth system of equations with box constraints is described. The method is an affine-scaling
trust-region method. All iterates generated by this method are strictly feasible. In this way, possible domain violations
outside or on the boundary of the box are avoided. The method is shown to have strong global and local convergence properties
under suitable assumptions, in particular, when the method is used with a special scaling matrix. Numerical results are presented
for a number of problems arising from different areas. 相似文献