Spin-dependent electron-hole capture kinetics in luminescent conjugated polymers

被引：88

作者：

Karabunarliev, S

Bittner, ER

机构：

[1] Univ Houston, Dept Chem, Houston, TX 77204 USA

[2] Univ Houston, Ctr Mat Chem, Houston, TX 77204 USA

来源：

PHYSICAL REVIEW LETTERS | 2003年 / 90卷 / 05期

关键词：

D O I：

10.1103/PhysRevLett.90.057402

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

The recombination of electron-hole pairs injected in extended conjugated systems is modeled as a multistep interconversion relaxation in monoexcited electronic state space, mediated by electron-phonon coupling. The computed ratio of triplet-to-singlet exciton formation times r=tau(T)/tau(S) increases from 0.9 for a model dimer to 2.5 for a 32-unit chain, in good agreement with recent experiments. We rationalize the conjugation-length dependence of r in terms of spin-specific energetics and mutual vibronic coupling of the excited states.

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页数：4

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