centre of symmetry

In physics, symmetry refers to the property where an object's characteristics remain unchanged after undergoing specific transformations. This concept is fundamental to understanding the laws of physics, including relativity and quantum mechanics. Symmetry operations, such as rotation or reflection, can be applied to objects like squares or circles, and if the object appears identical after the operation, it exhibits symmetry.1

In the context of crystals, a center of symmetry exists if a line drawn from any point on the surface through the crystal's center leads to an identical point equidistant from the center. This is equivalent to an inversion operation. The presence and types of symmetry elements, including rotation axes, rotoinversion axes, and mirror planes, define the 32 crystal classes, which are further grouped into six crystal systems.2