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A molecule is chiral if there is another molecule—in reality or in potential—that is of identical composition, but which is arranged in a non-superposable mirror image configuration. The presence of an asymmetric carbon atom is a main structural feature that induces chirality in molecules, but not the only one (see below).〔''Organic Chemistry'' (4th Edition) Paula Y. Bruice.〕〔''Organic Chemistry'' (3rd Edition) Marye Anne Fox ,James K. Whitesell.〕 Human hands are the most universally recognized example of chirality: the left hand is a non-superposable mirror image of the right hand; no matter how the two hands are oriented, it is impossible for all the major features of both hands to coincide. The term ''chirality'' is derived from the Greek word for hand, χειρ (kheir). It is a mathematical approach to the concept of "handedness". Conversely, an achiral object, such as an atom, is symmetric; its mirror image is not truly opposite, but rather is indistinguishable from the original. In chemistry, chirality usually refers to molecules. Two mirror images of a chiral molecule are called enantiomers or optical isomers. Pairs of enantiomers are often designated as "right-" and "left-handed". Molecular chirality is of interest because of its application to stereochemistry in inorganic chemistry, organic chemistry, physical chemistry, biochemistry, and supramolecular chemistry. == History == The term ''optical activity'' is derived from the interaction of chiral materials with polarized light. In a solution, the (−)-form, or levorotatory form, of an optical isomer rotates the plane of a beam of linearly polarized light counterclockwise. The (+)-form, or dextrorotatory form, of an optical isomer does the opposite. The property was first observed by Jean-Baptiste Biot in 1815, and gained considerable importance in the sugar industry, analytical chemistry, and pharmaceuticals. Louis Pasteur deduced in 1848 that this phenomenon has a molecular basis. Artificial composite materials displaying the analog of optical activity but in the microwave region were introduced by J.C. Bose in 1898, and gained considerable attention from the mid-1980s. The term ''chirality'' itself was coined by Lord Kelvin in 1894. Different enantiomers or diastereomers of a compound were formerly called optical isomers due to their different optical properties. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Chirality (chemistry)」の詳細全文を読む スポンサード リンク
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