Term: chirality axis
https://doi.org/10.1351/goldbook.C01059

Definition:
An axis about which a set of ligands is held so that it results in a spatial arrangement which is not superposable on its mirror image. For example with an allene abC=C=Ccd the chiral axis is defined by the C=C=C bonds; and with an ortho-substituted biphenyl the atoms C-1, C-1', C-4 and C-4' lie on the chiral axis.

Related Terms:
1) ligands (http://doi.org/10.1351/goldbook.L03518).
2) chiral (http://doi.org/10.1351/goldbook.C01057).

Source: PAC, 1996, 68, 2193. 'Basic terminology of stereochemistry (IUPAC Recommendations 1996)' on page 2203 (https://doi.org/10.1351/pac199668122193)

Citation: 'chirality axis' 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.C01059

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