V2B−$V_{\text{2B}}^-$andV2B+$V_{\text{2B}}^+$with their satellite structure. The equidistant spacing is the fingerprint of vibronic modes.[34,40]The inset shows the linear regression fitted to the relative peak voltages for negative (filled circles) and positive (open circles) bias. The obtained slopes are indicated. As the vibronic states undergo the same gating as O2B, the unipolar transport model can be applied. We obtain α = 0.65 ± 0.01 andEν= 20.1 ± 0.6 meV. Note, that the relative peak intensities for both bias polarities are almost identical in agreement with unipolar transport.
