Enantiomerism / Chirality

CORE DEFINITION

Enantiomers (English: Enantiomer (/ɪˈnæntiəmər, ɛ-, -tioʊ-/)), also known as optical isomers, mirror-image isomers, or antipodes, are stereoisomers that are non-superimposable mirror images of each other and have different optical properties. IUPAC does not recommend the term 'optical isomer'. Molecules that are mirror images. An asymmetric carbon atom is bonded to four different atoms or groups, and the asymmetric carbon is the chiral center. When there are n chiral centers, there are at most 2^n stereoisomers. Derived from Greek, a pair of substances that have a mirror-image relationship like left and right hands. No matter how they are arranged, these mirror images cannot become the same object. A substance with a plane of symmetry cannot be an enantiomer because it is identical to its mirror image. Enantiomers of molecules like lactic acid have exactly the same chemical properties, except for reactions with other asymmetric molecules and interaction with polarized light. Enantiomers are important in crystallography because many crystals are composed of alternating right-handed and left-handed forms of individual molecules. A complete description of a crystal requires explaining how these forms are mixed with each other.