Term: asymmetric
https://doi.org/10.1351/goldbook.A00478

Definition:
Lacking all symmetry elements (other than the trivial one of a one-fold axis of symmetry), i.e. belonging to the symmetry point group C1. The term has been used loosely (and incorrectly) to describe the absence of a rotation–reflection axis (alternating axis) in a molecule, i.e. as meaning chiral, and this usage persists in the traditional terms asymmetric carbon atom, asymmetric synthesis, asymmetric induction, etc.

Related Terms:
1) point group (http://doi.org/10.1351/goldbook.P04703).
2) chiral (http://doi.org/10.1351/goldbook.C01057).
3) asymmetric carbon atom (http://doi.org/10.1351/goldbook.A00479).
4) asymmetric synthesis (http://doi.org/10.1351/goldbook.A00484).
5) asymmetric induction (http://doi.org/10.1351/goldbook.A00483).

Source: Blue Book, p. 480 (https://www.acdlabs.com/iupac/nomenclature/)

Citation: 'asymmetric' 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.A00478

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