Improvement of the fluorescence quantum yield of triphenylene by the rotational effect of 4-(trimethylsilyl)phenyl groups

The fluorescence quantum yield of triphenylene is low because the transition moment between the HOMOs and the LUMOs is negligibly small. To improve the fluorescence quantum yield, break of the symmetrical structure of triphenylene is necessary. We found that the rotational effect of the 4-(trimethylsilyl)phenyl groups of 2,3,6,7,10,11-hexakis[4-(trimethylsilyl)phenyl]triphenylene is effective to break the symmetry in spite of the symmetrical structure, leading to improvement of the fluorescence quantum yield.