38446-40-1Relevant articles and documents
π-π and σ-π interactions in α,ω-Di-(9-anthryl) and Di-(1-naphthyl) oligosilanes studied by time-resolved fluorescence in solution
Karatsu, Takashi,Shibata, Toshifumi,Nishigaki, Atsuko,Kitamura, Akihide,Hatanaka, Yusuke,Nishimura, Yoshinobu,Sato, Shin-Ichiro,Yamazaki, Iwao
, p. 12184 - 12191 (2007/10/03)
The photophysical properties of two series of oligosilanes, (1-naphthyl)-(SiMe2)n-(1-naphthyl) (1-5) and (9-anthryl)-(SiMe2)n-(9-anthryl) (6-10) with n = 1-4 and 6, were investigated. In these compounds, two types of interactions, a π-π interaction between two aromatic groups and a σ-π interaction between aromatics and a silicon chain unit, were observed. Intramolecular excimer emission was observed in cyclohexane when n ≥ 2. The strongest excimer emission of 2 and 7 is different from the Hirayama rule (n = 3) proposed for carbon analogues and also shows that intramolecular cycloaddition is minor. The time-resolved fluorescence spectra of an anthryl series revealed that the time constant of excimer formation varied depending on the chain length (82-152 ps). In the cases of 4, 5, and 10, charge-transfer (CT) emission was observed in acetonitrile or THF. The time constant of the CT-state formation for 10 was relatively slow (45 ps), which may indicate a conformational change. Monomer emission from the locally excited state was observed for 1 and 6 in both cyclohexane and acetonitrile.
