Wull{shape and Density Deviation
نویسنده
چکیده
Recent results on sphere packings show a remarkable relation between dense nite sphere packings and concepts of crystallography, such as the Gibbs{Curie surface energy and the Wull{shape for ideal crystals and quasicrystals ((W2], W3], S], BB], BS1] and BS2]). The previous papers mainly considered applications. Here we prove some basic properties of the tools, in particular the density deviation and the resulting Wull{shape for periodic structures. We give stability results for increasing parameter %. Finally we show for some other concepts that they are not useful for application to crystallography, because they do not lead to polytopal asymptotic shapes.
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