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Extreme electron polaron spatial delocalization in ?-conjugated materials.

ABSTRACT: The electron polaron, a spin-1/2 excitation, is the fundamental negative charge carrier in ?-conjugated organic materials. Large polaron spatial dimensions result from weak electron-lattice coupling and thus identify materials with unusually low barriers for the charge transfer reactions that are central to electronic device applications. Here we demonstrate electron polarons in ?-conjugated multiporphyrin arrays that feature vast areal delocalization. This finding is evidenced by concurrent optical and electron spin resonance measurements, coupled with electronic structure calculations that suggest atypically small reorganization energies for one-electron reduction of these materials. Because the electron polaron dimension can be linked to key performance metrics in organic photovoltaics, light-emitting diodes, and a host of other devices, these findings identify conjugated materials with exceptional optical, electronic, and spintronic properties.

SUBMITTER: Rawson J

PROVIDER: S-EPMC4653201 | biostudies-literature | 2015 Nov

REPOSITORIES: biostudies-literature

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Extreme electron polaron spatial delocalization in π-conjugated materials.

Rawson Jeff J Angiolillo Paul J PJ Therien Michael J MJ

Proceedings of the National Academy of Sciences of the United States of America 20151028 45

The electron polaron, a spin-1/2 excitation, is the fundamental negative charge carrier in π-conjugated organic materials. Large polaron spatial dimensions result from weak electron-lattice coupling and thus identify materials with unusually low barriers for the charge transfer reactions that are central to electronic device applications. Here we demonstrate electron polarons in π-conjugated multiporphyrin arrays that feature vast areal delocalization. This finding is evidenced by concurrent opt ...[more]

PMID: 26512097

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