Atoms or groups of a molecule which are related by an
n-fold rotation axis (
n = 2, 3, etc.) are called homotopic. For example,
chiral tartaric acid
(
axis), chloroform
(
axis) and cyclohexaamylose (α-cyclodextrin,

axis) have respectively two homotopic carboxyl groups, three homotopic chlorine atoms
and six homotopic
d-glucose residues.
Source:
PAC, 1996, 68, 2193
(Basic terminology of stereochemistry (IUPAC Recommendations 1996))
on page 2210
Cite as:
IUPAC. Compendium of Chemical Terminology, 2nd ed. (the "Gold Book"). Compiled by
A. D. McNaught and A. Wilkinson. Blackwell Scientific Publications, Oxford (1997).
XML on-line corrected version: http://goldbook.iupac.org (2006-) created by M. Nic,
J. Jirat, B. Kosata; updates compiled by A. Jenkins. ISBN 0-9678550-9-8.
https://doi.org/10.1351/goldbook.