Unconventional Current Scaling and Edge Effects for Charge Transport through Molecular Clusters

Veronika Obersteiner, Georg Huhs, Nick Papior, Egbert Zojer

Research output: Contribution to journalArticleResearchpeer-review

Abstract

Metal-molecule-metal junctions are the key components of molecular electronics circuits. Gaining a microscopic understanding of their conducting properties is central to advancing the field. In the present contribution, we highlight the fundamental differences between single-molecule and ensemble junctions focusing on the fundamentals of transport through molecular clusters. In this way, we elucidate the collective behavior of parallel molecular wires, bridging the gap between single molecule and large-area monolayer electronics, where even in the latter case transport is usually dominated by finite-size islands. On the basis of first-principles charge-transport simulations, we explain why the scaling of the conductivity of a junction has to be distinctly nonlinear in the number of molecules it contains. Moreover, transport through molecular clusters is found to be highly inhomogeneous with pronounced edge effects determined by molecules in locally different electrostatic environments. These effects are most pronounced for comparably small clusters, but electrostatic considerations show that they prevail also for more extended systems.

Original languageEnglish
Pages (from-to)7350-7357
Number of pages8
JournalNano Letters
Volume17
Issue number12
DOIs
Publication statusPublished - 13 Dec 2017

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Keywords

  • ballistic transport
  • collective electrostatic effects
  • density functional theory
  • dipoles
  • molecular clusters
  • Molecular electronics

ASJC Scopus subject areas

  • Bioengineering
  • Chemistry(all)
  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanical Engineering

Fields of Expertise

  • Advanced Materials Science

Treatment code (Nähere Zuordnung)

  • Basic - Fundamental (Grundlagenforschung)

Cooperations

  • NAWI Graz

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