光応答性有機分子

Abstract

In the context of the importance of photoregulation of functions of organic substances, recent developement of photochromic molecules is described, focusing attention on the following topics.a) New photochromic compounds appearring in recent literatures. b) Molecular and environment design for getting the kinetic stability of photochrome isomers. c) What kind of property of materials, into which a photochromic molecule is incorporated, can be regulated by the photoisomerization of the chromophore ? d) Hitherto unknown phenomenon accompanying photochromism.Successful example for b) is heteroaromatic homologues of fulgide system which reveales a remarkable kinetic stability of the colored form and is immune to fatigue. A variety of properties of polymers, which are photochemically regulated, are related closely to the fundamental character of the photochromism of chromophoric unit in the polymer. Photo-voltaic phenomenon of the thin film of triphenylformazan is a unique two photon process consisting of photoisomerization of the red-form to the yellow-form and the successive photo-ionization of the latter.