Optical Properties of Disilane-Bridged Donor–Acceptor Architectures: Strong Effect of Substituents on Fluorescence and Nonlinear Optical Properties

Abstract

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.

Unusual Reactivity of Group 14 Hydrides toward Organic Halides: Synthetic Studies and Application to Functional Materials

“…These unsymmetrical substituted disilanes were obtained by coupling 1 aryl 1,1,2,2 tetramethyldisilanes with aryl iodides in the presence of a Pd catalyst. 27 We studied their photophysical properties and second order nonlinear optical responses (second harmonic generation (SHG)) by a powder method (Figure 4). Compounds 71 76 are stable thermally and chemically, and exhibit a strong emission at room temperature.…”

Nonlinear Optical Properties of Organosilicons: Intramolecular Charge Transfer in Pyridyldisilanes with a Donor‐Acceptor Linker

“…Nishihara et al . have reported that the disilane‐bridged donor‐acceptor asymmetric diphenyldisilane derivatives, with p ‐ N , N ‐dimethylamino and o ‐cyano substituents, exhibits optical second harmonic generation (the calculated first hyperpolarizability is about 1.6×10 −30 esu, five times larger than that of urea). It is demonstrated that the asymmetric disilanes are interesting building blocks for constructing NLO materials.…”

ABAB Phthalocyanines: Scaffolds for Building Unprecedented Donor-π-Acceptor Chromophores

“…Conjugated donor–π–acceptor ensembles are core structures for several purposes that range from basic research to real applications, namely, as mimics of the natural photosynthetic system, chromophores to study a wide variety of non‐linear optical (NLO) phenomena, and active molecules in organic and hybrid dye‐sensitized solar cells (DSSCs) . In particular, the key to achieve highly efficient DSSCs lies in the preparation of stable organic dyes with an appropriate push–pull pattern that facilitates electron injection into the conduction band of a mesoporous TiO 2 semiconductor .…”