Oscillating Interatomic Potentials and Growth of Icosahedral Quasicrystals

The crucial role of frustration in atomic ordering for quasicrystal formation is demonstrated within a simple pmodel for three-dimensional growth of icosahedral quasicrystals in binary alloys (up to $2\times {10}^6$ atoms). Two features of the model are important: (1) The ratio of atomic sizes is the one typical for the CsCl structure and (2) the interatomic potential is an oscillating function of interatomic distances (those oscillations cause frustration in atomic ordering). It is shown that different potentials result in different faceting of the grown clusters. Phasonic jumps and the phasonic relaxation in the clusters are discussed.