德国拜罗伊特大学Prof. Smaalen学术报告(II)

Prof. Dr. Sander van Smaalen Laboratory of Crystallography, University of Bayreuth, 95440, Bayreuth, Germany Topic: Introduction to aperiodic crystals Abstract: Aperiodic crystals are materials possessing crystalline properties,but lacking three-dimensional translational symmetry.They include quasicrystals,incommensurately modulated crystals and incommensurately composite crystals.Crystals structures of incommensurately modulated compounds and composite crystals can most favorably be described with aid of superspace, a special variety of four-dimensional or higher-dimensional space. The concept of superspace was originally introduced by P.M. de Wolff, A. Janner and T. Janssen, and in the early 1980s it was applied to the structural analysis of a series of modulated crystals by A. Yamamoto. Here, an overview will be given of the crystal structures of the various types of aperiodic crystals, and consequences will be discussed of this special kind of order for physical properties. Further Reading: 1. S. van Smaalen: “Incommensurate Crystallography.” Oxford University Press, Oxford (2007). Published as paperback (with corrections)2012. 2. S. van Smaalen, “An elementary introduction to superspace crystallography.” Z. Kristallogr. 219(2004)681. 3. S. van Smaalen, B. J. Campbell and H. T. Stokes, “Equivalence of superspace groups.” Acta Crystallogr. A 69(2013)75.

 时间：2015年4月10日星期五，上午10:00

地点：博逸楼 401 会议室

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