Quasicrystalleja

Quasicrystals are solid materials that possess atomic arrangements that are ordered but not periodic. Unlike conventional crystals, which have a repeating unit cell that tiles space without gaps or overlaps, quasicrystals exhibit a long-range orientational order that is not translationally periodic. This means that while there is a predictable pattern in their structure, it does not repeat itself in a simple, regular manner like the arrangement of atoms in a typical crystal.

The discovery of quasicrystals in 1982 by Dan Shechtman, who was awarded the Nobel Prize in Chemistry in 2011 for this work, challenged the long-held understanding of crystallography. Before quasicrystals, it was believed that the only possible ordered atomic structures were periodic. Quasicrystals exhibit symmetries, such as five-fold rotational symmetry, which are forbidden in traditional crystalline structures according to classical crystallography principles.

Despite their non-periodic nature, quasicrystals are ordered, meaning their atomic positions are not random. They can be described using mathematical concepts like Penrose tilings, which are non-periodic tessellations of a plane by a set of geometric shapes. Quasicrystals can be formed from various elements and alloys, often involving metals. Their unique properties, including high hardness, low friction, and excellent thermal and electrical insulation, make them of interest for potential applications in areas such as coatings, specialized tools, and alloys.