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Inelastic current-voltage characteristics of atomic and molecular junctions

Yu-Chang Chen·Michael Zwolak·Massimiliano Di Ventra
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Abstract

We report first-principles calculations of the inelastic current-voltage (I-V) characteristics of a gold point contact and a molecular junction in the nonresonant regime. Discontinuities in the I-V curves appear in correspondence to the normal modes of the structures. Due to the quasi-one-dimensional nature of these systems, specific modes with large longitudinal component dominate the inelastic I-V curves. In the case of the gold point contact, our results are in good agreement with recent experimental data. For the molecular junction, we find that the inelastic I-V curves are quite sensitive to the structure of the contact between the molecule and the electrodes thus providing a powerful tool to extract the bonding geometry in molecular wires.

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Yu-Chang Chen, Michael Zwolak, Massimiliano Di Ventra. 2005-03-08. Inelastic current-voltage characteristics of atomic and molecular junctions. https://doi.org/10.1021/nl0490927

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