Epäkiteinen

Epäkiteinen is a Finnish adjective that translates to "amorphous" in English. It describes materials that lack a long-range, ordered structure at the atomic or molecular level. Unlike crystalline solids, where atoms or molecules are arranged in a repeating, regular pattern, amorphous materials have a disordered arrangement. This can be visualized as a jumbled, random packing of constituent particles.

Many common materials exhibit amorphous forms. Glass, for instance, is a classic example of an amorphous solid. When silica (silicon dioxide) is heated and then cooled rapidly, the atoms do not have sufficient time to arrange themselves into the ordered structure of quartz, resulting in a glassy, amorphous state. Other examples include certain polymers, where the long molecular chains are entangled and lack precise orientation, and some types of plastics.

The lack of a defined crystal structure gives amorphous materials distinct properties compared to their crystalline counterparts. They often exhibit isotropic behavior, meaning their physical properties are the same in all directions, unlike many crystals which can be anisotropic. Amorphous solids may also have lower melting points or exhibit a glass transition temperature instead of a sharp melting point. The term "epäkiteinen" is primarily used in scientific and technical contexts in Finland to describe this specific material characteristic.