Dataset for "Measuring competing outcomes of a single-molecule reaction reveals classical Arrhenius chemical kinetics"

Dataset

Description

This dataset contains data supporting the results presented in the paper "Measuring competing outcomes of a single-molecule reaction reveals classical Arrhenius chemical kinetics". It contains the analysed data of single toluene molecule manipulation experiments carried out on the Si(111)-7x7 surface in Excel spreadsheet format. The experiments span the injection bias voltage range of +1.4 eV to +2.2 eV, the injection current range of 25 pA to 900 pA, and three separate injection locations: on top of an adatoms, a molecule, and a restaom. The dataset contains the extracted manipulation probabilities and branching ratios as well as spectroscopy data above faulted corner and toluene faulted middel sites.

The atomic resolution of scanning probe microscopy and its ability to excite a molecule locally can give control over the probability of inducing a single-outcome single-molecule reaction. The paper shows our control over the branching ratio between a single-molecule reaction that exhibits two reaction outcomes. Toluene molecules chemisorbed on the Si(111)-7x7 surface at room temperature are induced to react, one at a time, by the tunnelling current of a scanning tunnelling microscope: the molecule either desorbs, or switches to an adjacent surface site. Above a voltage threshold set by the electronics structure of the molecule, we see that the branching ratio between these two outcomes is dependent on the excess energy the exciting electron carries. Using known values and ab inito DFT calculations support our findings, a simple Arrhenius model is developed to describe the intermediate physisorbed state that leads to either desorption or site-switching. We conclude that the excess energy of the exciting electron leads to a heating of the intermediate physisorbed state and hence, via their energy barrier and pre-factors, gives control over the two reaction outcomes.
Date made available28 Nov 2024
PublisherUniversity of Bath

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