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Author(s) -
Würthner Frank,
Wortmann Rüdiger,
Meerholz Klaus
Publication year - 2002
Publication title -
chemphyschem
Language(s) - English
Resource type - Reports
SCImago Journal Rank - 1.016
H-Index - 140
eISSN - 1439-7641
pISSN - 1439-4235
DOI - 10.1002/1439-7641(20020118)3:1<1::aid-cphc1>3.0.co;2-u
Subject(s) - photorefractive effect , photoexcitation , space charge , materials science , chemical physics , polarizability , optoelectronics , optics , electron , chemistry , nanotechnology , atomic physics , physics , organic chemistry , molecule , quantum mechanics , excited state
The cover picture shows insights into a photorefractive composite material, showing all important molecular‐scale processes which take place upon illumination. The left side shows the interaction of a laser beam with the charge transfer complex generated between the electron‐rich merocyanine dye ATOP (a focus of this Review) and the electron‐poor TNFM. After such photoexcitation, charge separation occurs and the positive charge (hole) can migrate along the conductive polymer PVK: Charge motion creates a space‐charge field. The right side shows both the interaction of the ATOP dye with the space‐charge field and the most serious problem facing nonlinear optical dye‐based materials, the formation of antiparallel dimer aggregates. For this reason, the exploitation of the full molecular (hyper)polarizability is not achieved for high dye loadings demanded of in usable materials. All these topics, and ways to achieve the highest‐possible refractive index modulation efficiency in photorefractive materials, are covered in the Review by Würthner, Wortmann, and Meerholz on pages 17–31.