Dynamics of conformational relaxation in photoexcited oligofluorenes and polyfluorene

被引：41

作者：

Hintschich, S. I. ^{[1
]}

Dias, F. B. ^{[1
]}

Monkman, A. P. ^{[1
]}

机构：

[1] Univ Durham, Dept Phys, Organ Electroact Mat Grp, Durham DH1 3LE, England

来源：

PHYSICAL REVIEW B | 2006年 / 74卷 / 04期

关键词：

D O I：

10.1103/PhysRevB.74.045210

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

In order to disentangle the relaxation effects of exciton migration and conformational rearrangement, a comparative study of a polyfluorene derivative and short oligofluorenes is carried out. We probe their long-time time-dependent relaxation in dilute solution using picosecond single photon counting and streak camera techniques. Conformational relaxation is found in oligo- and polyfluorenes. Oligofluorene relaxation is purely conformational: time scales vary between 10 and 300 ps becoming faster with decreasing chain length and solvent viscosity or increasing temperature. While a rigid ladder-type polymer in solution does not show any picosecond relaxation, polyfluorene in solution exhibits fluorescence dynamics indicating both, conformational relaxation and exciton migration.

引用

页数：10

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