Department of Chemistry, School of Science, The University of Tokyo , 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
J Am Chem Soc. 2015 Jan 28;137(3):1024-7. doi: 10.1021/ja511177e. Epub 2015 Jan 13.
A series of disilane-bridged donor-acceptor architectures 1-9 containing strong electron-donating and -withdrawing substituents were designed and synthesized in acceptable yields. The substituents substantially affected the fluorescence and nonlinear optical properties of the compounds. In the solid state, the compounds showed purple-blue fluorescence (λ(em) = 360-420 nm) with high quantum yields (up to 0.81). Compound 3, which had p-N,N-dimethylamino and o-cyano substituents, exhibited optical second harmonic generation (activity 2.9 times that of urea, calculated molecular hyperpolarizability β = 1.6 × 10(-30) esu) in the powder state. Density functional theory calculations for the ground and excited states indicated that both the locally excited state and the intramolecular charge transfer excited state make important contributions to the luminescence behavior.
一系列含有强供电子和吸电子取代基的二硅烷桥联给体-受体结构 1-9 以可接受的产率设计并合成。取代基显著影响了化合物的荧光和非线性光学性质。在固态下，化合物表现出紫色-蓝色荧光（λ（em）= 360-420nm），量子产率高（高达 0.81）。具有对-N,N-二甲基氨基和邻氰基取代基的化合物 3 在粉末状态下表现出光学二次谐波产生（活性是尿素的 2.9 倍，计算的分子超极化率β= 1.6×10（-30）esu）。基态和激发态的密度泛函理论计算表明，局域激发态和分子内电荷转移激发态都对发光行为有重要贡献。
