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Diarylethene Molecular Photoswitches
Concepts and Functionalities
Masahiro Irie
Author
Masahiro Irie
Professor emeritus Kyushu University Japan
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Print ISBN: 978‐3‐527‐34640‐0 ePDF ISBN: 978‐3‐527‐34642‐4 ePub ISBN: 978‐3‐527‐82286‐7 oBook ISBN: 978‐3‐527‐82285‐0
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Preface
Molecules capable of reversible photoswitching between two isomers having different absorption spectra are called photochromic molecules or molecular photoswitches. The two isomers differ from each other not only in their absorption and fluorescence spectra, but also in their refractive indices, dielectric constants, oxidation/reduction potentials, and geometrical structures. These photoswitchable bistable molecules are applied to construct photonic devices, such as erasable optical memory media and optical switch elements. Although the first finding of photoswitchable molecules can be traced back to the middle of nineteenth century, they are still awaiting their time to go on the stage of photonics devices in wide use.
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