Interpretation of Stochastic Events in Single-Molecule Measurements of Conductance and Transition Voltage Spectroscopy

The first simultaneous measurements of transition voltage (Vt) spectroscopy (TVS) and conductance (G) histograms (Guo et al., J. Am. Chem. Soc.2011, 133, 19189) form a great case for studying stochastic effects, which are ubiquitous in molecular junctions. Here an interpretation of those data is proposed that emphasizes the different physical content of Vt and G and reveals that fluctuations in the molecular orbital alignment have a significantly larger impact on G than initially claimed. The present study demonstrates the usefulness of corroborating statistical information on different transport properties and gives support to TVS as a valuable investigative tool.