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Structure-Directed Exciton Dynamics in Templated Molecular Nanorings.

ABSTRACT: Conjugated polymers with cyclic structures are interesting because their symmetry leads to unique electronic properties. Recent advances in Vernier templating now allow large shape-persistent fully conjugated porphyrin nanorings to be synthesized, exhibiting unique electronic properties. We examine the impact of different conformations on exciton delocalization and emission depolarization in a range of different porphyrin nanoring topologies with comparable spatial extent. Low photoluminescence anisotropy values are found to occur within the first few hundred femtoseconds after pulsed excitation, suggesting ultrafast delocalization of excitons across the nanoring structures. Molecular dynamics simulations show that further polarization memory loss is caused by out-of-plane distortions associated with twisting and bending of the templated nanoring topologies.

SUBMITTER: Gong JQ

PROVIDER: S-EPMC4418736 | biostudies-literature | 2015 Mar

REPOSITORIES: biostudies-literature

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Structure-Directed Exciton Dynamics in Templated Molecular Nanorings.

Gong Juliane Q JQ Parkinson Patrick P Kondratuk Dmitry V DV Gil-Ramírez Guzmán G Anderson Harry L HL Herz Laura M LM

The journal of physical chemistry. C, Nanomaterials and interfaces 20150226 11

Conjugated polymers with cyclic structures are interesting because their symmetry leads to unique electronic properties. Recent advances in Vernier templating now allow large shape-persistent fully conjugated porphyrin nanorings to be synthesized, exhibiting unique electronic properties. We examine the impact of different conformations on exciton delocalization and emission depolarization in a range of different porphyrin nanoring topologies with comparable spatial extent. Low photoluminescence ...[more]

PMID: 25960822

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