0 a solid substance with a structure that contains patterns and repetition but is not fully symmetrical (= exactly matching) like a crystal
In other words, we view a fully periodic set, or 'crystal', as a special kind of 'quasicrystal'.
One of the commonly used definitions of a quasicrystal is that of an atomic structure which has a discrete component in its diffraction spectrum.
In particular, they can be viewed as a mathematical abstraction of the set of atomic positions of a physical quasicrystal (at zero temperature, or at a given instant of time).
Does there exist a nice characterization of the 'simplest' aperiodic sets, which might be used to define a notion of 'perfectly ordered quasicrystal'?
This natural quasicrystal exhibits high crystalline quality, equalling the best artificial examples.
Its underlying symmetry is also fivefold but it is not a quasicrystal.
Glotzer and collaborators also hold the record for the densest tetrahedron packing and discovered that hard tetrahedrons can self-assemble into a dodecagonal quasicrystal.
It forms an aperiodic pattern known as a quasicrystal.