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Alkylamide-substituted tetraphenylethylene: three modes of fluorescence based on a hydrogen-bonded excimer
Takashi Takeda1, Shunsuke Yamamoto, Masaya Mitsuishi
1Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Katahira 2-1-1, Aoba-ku, Sendai, 980-8577 Miyagi, Japan. takeda@tagen.tohoku.ac.jp.
Abstract:
Three modes of emission, with different intensities and wavelengths were observed in tetraphenylethylenetetraamide 1 depending on the solvent, concentration and continuous irradiation with light, where intermolecular hydrogen bonds between amide units played a significant role. Limitation of the motility of molecule 1 in the excited state by intermolecular hydrogen bonding is the key for observation of fluorescence even in the solution and transformation to the corresponding 9,10-diphenylphenanthrene derivative.
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