Engineering nanometre-scale coherence in soft matter.

Journal Article

Electronic delocalization in redox-active polymers may be disrupted by the heterogeneity of the environment that surrounds each monomer. When the differences in monomer redox-potential induced by the environment are small (as compared with the monomer-monomer electronic interactions), delocalization persists. Here we show that guanine (G) runs in double-stranded DNA support delocalization over 4-5 guanine bases. The weak interaction between delocalized G blocks on opposite DNA strands is known to support partially coherent long-range charge transport. The molecular-resolution model developed here finds that the coherence among these G blocks follows an even-odd orbital-symmetry rule and predicts that weakening the interaction between G blocks exaggerates the resistance oscillations. These findings indicate how sequence can be exploited to change the balance between coherent and incoherent transport. The predictions are tested and confirmed using break-junction experiments. Thus, tailored orbital symmetry and structural fluctuations may be used to produce coherent transport with a length scale of multiple nanometres in soft-matter assemblies, a length scale comparable to that of small proteins.

Full Text

Duke Authors

Cited Authors

  • Liu, C; Xiang, L; Zhang, Y; Zhang, P; Beratan, DN; Li, Y; Tao, N

Published Date

  • October 2016

Published In

Volume / Issue

  • 8 / 10

Start / End Page

  • 941 - 945

PubMed ID

  • 27657870

Electronic International Standard Serial Number (EISSN)

  • 1755-4349

International Standard Serial Number (ISSN)

  • 1755-4330

Digital Object Identifier (DOI)

  • 10.1038/nchem.2545

Language

  • eng