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This content will become publicly available on June 1, 2023

Title: Single-Molecule Kinetic Analysis of Oxygenation of Co(II) Porphyrin at the Solution/Solid Interface
Kinetic analysis of surface reactions at the single molecule level is important for understanding the influence of the substrate and solvent on reaction dynamics and mechanisms, but it is difficult with current methods. Here we present a stochastic kinetic analysis of the oxygenation of cobalt octaethylporphyrin (CoOEP) at the solution/solid interface by monitoring fluctuations from equilibrium using scanning tunneling microscopy (STM) imaging. Image movies were used to monitor the oxygenated and deoxygenated state dwell times. The rate constants for CoOEP oxygenation are ka = 4.9×10-6 s-1∙torr-1 and kd = 0.018 s-1. This is the first use of stochastic dwell time analysis with STM to study a chemical reaction and the results suggest that it has great potential for application to a wide range of surface reactions. Expanding these stochastic studies to further systems is key to unlocking kinetic information for surface confined reactions at the molecular level -- especially at the solution/solid interface.
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The Journal of Physical Chemistry Letters
Page Range or eLocation-ID:
4918 to 4923
Sponsoring Org:
National Science Foundation
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