Orthorombinainen

Orthorhombic is a crystal system characterized by three unequal crystallographic axes that are mutually perpendicular. This means the unit cell has three distinct lengths, denoted as a, b, and c, where a ≠ b ≠ c, and the angles between them are all 90 degrees. It is one of the seven crystal systems and is a subdivision of the orthorhombic lattice.

The orthorhombic system is known for its lack of symmetry elements beyond a unit cell with mutually perpendicular axes. It does not possess rotational symmetry axes of higher order than two-fold (a diad axis) or mirror planes in combination with a unit cell that has three unequal axes and 90-degree angles. The simplest form in the orthorhombic system is the orthorhombic prism, which has rectangular faces.

Minerals crystallizing in the orthorhombic system include sulfur, olivine, barite, and topaz. The distinct physical properties of minerals in this system, such as their optical behavior and cleavage, are often a direct consequence of their orthorhombic crystal structure. The arrangement of atoms or molecules within the unit cell dictates these properties. For example, the refractive indices of light passing through an orthorhombic crystal will generally vary depending on the direction of propagation.