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Opposite Anisotropy Effects of Singlet and Triplet Exciton Diffusion in Tetracene Crystal.

ABSTRACT: We observe the diffusion anisotropy difference between singlet and triplet excitons in organic crystals; that is, singlet and triplet excitons may have completely different spatial direction preference for diffusion. This phenomenon can be ascribed to the distinct dependence of different excitonic couplings (Coulomb Förster vs. exchange Dexter) existing in singlet and triplet excitons on their intermolecular distance and intermolecular orientation. Such a discovery provides insights for understanding the fundamental photophysical process in a vast range of organic condensed-phase systems and optimizing the efficiency of organic optoelectronic materials.

SUBMITTER: Xie X

PROVIDER: S-EPMC5126140 | biostudies-literature | 2016 Jun

REPOSITORIES: biostudies-literature

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Opposite Anisotropy Effects of Singlet and Triplet Exciton Diffusion in Tetracene Crystal.

Xie Xiaoyu X Ma Haibo H

ChemistryOpen 20160218 3

We observe the diffusion anisotropy difference between singlet and triplet excitons in organic crystals; that is, singlet and triplet excitons may have completely different spatial direction preference for diffusion. This phenomenon can be ascribed to the distinct dependence of different excitonic couplings (Coulomb Förster vs. exchange Dexter) existing in singlet and triplet excitons on their intermolecular distance and intermolecular orientation. Such a discovery provides insights for understa ...[more]

PMID: 27933226

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