The nearly dispersionless, so-called “optical” vibrational modes observed by inelastic neutron scattering from icosahedral Al-Pd-Mn and Zn-Mg-Y quasicrystals are found to correspond well to modes of a continuum elastic sphere that has the same diameter as the corresponding icosahedral basic units of the quasicrystal. When the sphere is considered as free, most of the experimentally found modes ...

In this paper, we report atomic scale observations and formation mechanisms of a high-density antiphase boundaries (APBs) within an ultra-fine-grained Fe4Al13 intermetallic layer at Al/steel interface after heat treatment 596 °C. The results reveal that the APBs are formed by nucleation glide partial dislocations with Burgers vector b/3[010] (b = 12.47 Å). intensive activation locally transform...

A set of X-ray data collected on a fragment decagonite, Al 71 Ni 24 Fe 5 , the only known natural decagonal quasicrystal found in meteorite formed at beginning Solar System, allowed us to determine first structural model for quasicrystal. It is two-layer structure with columnar clusters arranged according pentagonal Penrose tiling. The showed peculiarities and slight differences respect those o...

Aperiodic algebras are infinite dimensional with generators corresponding to an element of the aperiodic set. These proved be useful tool in studying elementary excitations that can propagate multilayered structures and construction some integrable models quantum mechanics. Starting from works Patera Twarock we present three based on Fibonacci-chain quasicrystals: a quasicrystal Lie algebra, Wi...

2014 The regular deviations from the exact icosahedral symmetry, usually observed at the diffraction patterns of quasicrystal alloys, are analyzed. It is shown that shifting, splitting and asymmetric broadening of reflections can be attributed to crystalline phases with the cubic symmetry very close to the icosahedral one (such pseudo-icosahedral cubic approximants may be called the Fibonacci c...

We investigate a thin Sn film grown at elevated temperatures on the fivefold surface of an icosahedral AlCuFe quasicrystal by scanning tunneling microscopy (STM). At about one monolayer coverage, the deposited Sn is found to form a smooth film of height consistent with one-half of the lattice constant of the bulk Sn. Analysis based on the Fourier transform and autocorrelation function derived...