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.
@article{arxiv.cond-mat/0402536,
title = {Inelastic current-voltage characteristics of atomic and molecular junctions},
author = {Yu-Chang Chen and Michael Zwolak and Massimiliano Di Ventra},
journal= {arXiv preprint arXiv:cond-mat/0402536},
year = {2015}
}