Enantiomers

In chemistry, an enantiomer (/ɪˈnæntiəmər, ɛ-, -tioʊ-/ə-NAN-tee-ə-mər; from Greek ἐνάντιος (enántios), meaning 'opposite', and μέρος (méros), meaning 'part'), also known as an optical isomer, is one of two stereoisomers that are mirror images of each other that are non-superposable (not identical), much as one's left and right hands are the same except for being reversed along one axis (the hands cannot be made to appear identical simply by reorientation). A single chiral atom or similar structural feature in a compound causes that compound to have two possible structures which are non-superposable, each a mirror image of the other. Each member of the pair is termed an enantiomorph (enantio = opposite ; morph = form); the structural property is termed enantiomerism. The presence of multiple chiral features in a given compound increases the number of geometric forms possible, though there may be some perfect-mirror-image pairs.

Enantiopure compounds refer to samples having, within the limits of detection, molecules of only one chirality.

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