Mesogenic gold complexes showing aggregation-induced enhancement of phosphorescence in both crystalline and liquid-crystalline phases.

Faraday Discuss

Department of Applied Chemistry, College of Life Sciences, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu 525-8577, Japan.

Published: February 2017

Mesogenic Au complexes with a biphenyl core were synthesized as new AIEgens, and their thermodynamic and photophysical properties were discussed. Similar to Au complexes with a phenyl core which have been reported previously, the complexes with a short alkoxy chain formed dimers in the crystal form. However, the complexes with a long alkoxy chain formed two-dimensional layer structures through multiple intermolecular interactions in both the crystalline and liquid-crystalline (LC) phases. The present Au complexes showed a high thermochemical stability against thermal decomposition and a high thermodynamic stability of the LC phase. Moreover, these materials exhibited intensive phosphorescence with a large quantum yield (∼66%) in the crystals. In the crystal and LC phase with a layer structure, the phosphorescence intensity was enhanced only on aggregation. Thus, these mesogenic Au complexes can be expected to be useful as phosphorescent AIEgens.

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http://dx.doi.org/10.1039/c6fd00157bDOI Listing

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