Modulated Quasicrystals
نویسنده
چکیده
There is some confusion in the literature what “modulated quasicrystals” are: Some people treat “modulated quasicrystals” and “deformed model sets” as exchangeable termini (compare [6, 9, 5]), others claim that “[. . .] the projection method becomes powerless against incommensurate modulated structures” (e.g., [12, p. 148]). We use a mathematical approach and propose the following classification: While deformed model sets are characterised by a deformation that does not change the location of the Bragg peaks, a modulated phase yields “satellites” in the diffraction pattern and is achieved “by enlarging the internal space” with a torus.
منابع مشابه
Modulated Structures, Nanocrystals and Quasicrystals in Mg-Zn-Y Alloys
The formation of the icosahedral phase, BCC (Body centred cubic) phase and nanocrystals are seen in the as-cast alloy with nominal composition of Mg4Zn94Y2. FCC (face centred cubic) phase and modulated structures are formed in the alloys with higher Y content (10% and 25% Y respectively). These phases are analysed keeping in view their relation to the quasicrystals of the Mg-Zn-Y system.
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