Electron-vibrational relaxation of photoexcited polyfluorenes in the presence of chemical defects: A theoretical study

被引:34
作者
Franco, I
Tretiak, S
机构
[1] Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA
[2] Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA
[3] Abdus Salam Int Ctr Theoret Phys, I-34014 Trieste, Italy
关键词
D O I
10.1016/S0009-2614(03)00419-6
中图分类号
O64 [物理化学(理论化学)、化学物理学];
学科分类号
070304 ; 081704 ;
摘要
A quantum chemical semiempirical investigation of electron-vibrational dynamics of photoexcited conjugated polyfluorenes shows that delocalized electronic excitations dominate the absorption, whereas chemical defects (if present) dramatically impact the emission by trapping the photogenerated exciton into a localized state and acting as guest emitters at recombination. These results offer theoretical insight into the effect of non-quenching defect sites in conjugated polymers and explain the origin of a controversial low energy emission band frequently observed in bulk polyfluorene samples. (C) 2003 Elsevier Science B.V. All rights reserved.
引用
收藏
页码:403 / 408
页数:6
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