Pöörlemissümmeetriad

Pöörlemissümmeetriad describe the rotational symmetry of an object or shape. An object possesses rotational symmetry if it can be rotated by an angle less than 360 degrees about a central point and appear identical to its original orientation. The order of rotational symmetry is the number of times the object appears identical to itself during a full 360-degree rotation. For example, a square has rotational symmetry of order 4, meaning it looks the same after rotations of 90, 180, and 270 degrees. An equilateral triangle has rotational symmetry of order 3, appearing the same after rotations of 120 and 240 degrees. A circle has infinite rotational symmetry, as it appears identical after any rotation.

The axis of rotation is the imaginary line passing through the center of rotation. If the axis is perpendicular to the plane of the object, it is called a proper rotation. If the axis lies within the plane, it's sometimes referred to as an improper rotation, though this is less common when discussing simple rotational symmetry. In molecular chemistry, rotational symmetry is a fundamental concept used to classify molecules. For instance, a molecule with a C_n axis can be rotated by 360/n degrees around that axis and appear unchanged. This property influences a molecule's physical and chemical behavior, including its spectroscopic properties and interactions with other molecules. Understanding pöörlemissümmeetriad is crucial in fields such as geometry, crystallography, and quantum mechanics.