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arXiv · 1005.0529

Electrochemical control of quantum interference in anthraquinone-based molecular switches

Troels Markussen·Jakob Schiøtz·Kristian S. Thygesen
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Abstract

Using first-principles calculations we analyze the electronic transport properties of a recently proposed anthraquinone based electrochemical switch. Robust conductance on/off ratios of several orders of magnitude are observed due to destructive quantum interference present in the anthraquinone, but absent in the hydroquinone molecular bridge. A simple explanation of the interference effect is achieved by transforming the frontier molecular orbitals into localized molecular orbitals thereby obtaining a minimal tight-binding model describing the transport in the relevant energy range in terms of hopping via the localized orbitals. The topology of the tight-binding model, which is dictated by the symmetries of the molecular orbitals, determines the amount of quantum interference.

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Troels Markussen, Jakob Schiøtz, Kristian S. Thygesen. 2010-05-04. Electrochemical control of quantum interference in anthraquinone-based molecular switches. https://doi.org/10.1063/1.3451265

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