Term: chirality
https://doi.org/10.1351/goldbook.C01058

Definition:
The geometric property of a rigid object (or spatial arrangement of points or atoms) of being non-superposable on its mirror image; such an object has no symmetry elements of the second kind (a mirror plane, σ = S 1, a centre of inversion, i = S2, a rotation-reflection axis, S 2n). If the object is superposable on its mirror image the object is described as being achiral.

Related Terms:
1) handedness (http://doi.org/10.1351/goldbook.H02735).
2) superposability (http://doi.org/10.1351/goldbook.S06144).
3) inversion (http://doi.org/10.1351/goldbook.I03146).
4) achiral (http://doi.org/10.1351/goldbook.A00069).

Source: Blue Book, p. 479 (https://www.acdlabs.com/iupac/nomenclature/)

Citation: 'chirality' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.C01058

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