- 作者: 鄭宜明,吳以哲,賴金宏,浦士杰,周必泰,衛靖燕,余昭穎,林宜心,丁晴
- 作者服務機構: Department of Chemistry, National Taiwan University, Taipei 10617, Taiwan, R.O.C.
- 中文摘要: An azulenylosquaric dye (ASQ) has been synthesized to investigate its associated photophysical properties. ASQ is essentially nonluminescent (Φf < 3 × 10-6) in any solvent despite its very high absorption extinction coefficient (760 nm, ε ~ 8.2 × 104 M-1cm-1 in methanol). Femtosecond fluorescence upconversion, anisotropy kinetics and transient absorption experiments, in combination with the theoretical time-dependent DFT approach, leads us to conclude that the 760 nm absorption is ascribed to the fully allowed S0 → Sn (n ≧ 2) transition. The observed < 130 fs decay component is attributed to the Sn → S1 internal conversion, while the S1 → S0, with a slower radiative decay time (> 233 ns) undergoes a dominant radiationless deactivation process (710 ± 70 fs) possibly governed by strong interaction between S1 and S0 potential energy surfaces.
- 英文摘要: --
- 中文關鍵字: Fluorescence upconversion; Azulenylosquaric dye; Transient absorption; DFT; Internal conversion.
- 英文關鍵字: --