Term: half-chair
https://doi.org/10.1351/goldbook.H02715

Definition:
The conformation of a six-membered ring structure in which four contiguous atoms are in a plane and the other two atoms lie on opposite sides of the plane. H02715.png

Related Terms:
1) chair, boat, twist (http://doi.org/10.1351/goldbook.C00964).
2) conformation (http://doi.org/10.1351/goldbook.C01258).

Image: Not defined (https://goldbook.iupac.org/img/inline/H02715.png) 

Source: PAC, 1996, 68, 2193. 'Basic terminology of stereochemistry (IUPAC Recommendations 1996)' on page 2209 (https://doi.org/10.1351/pac199668122193)

Citation: 'half-chair' 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.H02715

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