Chirality

In chemistry, a molecule or ion is said to be chiral if it cannot be superposed on its mirror counterpart by any combination of rotations, translations, and conformational modifications. This geometric characteristic is known as chirality. The names are taken from the Ancient Greek (cheir) word for "hand," which is the archetypal example of an item possessing this feature. A chiral molecule or ion occurs in two stereoisomers that are mirror copies of each other, known as enantiomers; they are generally characterised as "right-handed" or "left-handed" by their absolute configuration or some other criterion. Except when interacting with other chiral molecules, the two enantiomers have identical chemical characteristics. They also share the same physical qualities, with the exception that they frequently exhibit opposing optical activity.