Butene Isomerization on Palladium Surfaces: Time-Dependent Monte Carlo Studies

A new time-dependent Monte Carlo approach, tdMC, is presented. This allows one to manage the quantum-chemical information relating to surface catalytic processes and rationalize, with atomistic dynamical perspectives, the corresponding reaction mechanism by providing descriptors that can be compared with experimentally obtained data. The approach, which falls into the more general microkinetic paradigm, is strictly self-consistent as it exploits information framed in just one computational method based on the density functional theory. The results simulated by the tdMC algorithm concern the isomerization of but-1-ene to cis- and trans-but-2-ene on Pd surfaces. This reaction was chosen mainly to focus on the development and implementation of the model as well as to point out the characteristics of the code and the soundness of the approach. In order to reach these goals, the simulated findings were compared to related experimental and computational literature data. From the study, it clearly emerges that the tdMC approach, although conceptually very straightforward and simple, is flexible enough to pinpoint the main characteristics of the reaction, which is just seemingly elementary and conversely governed by a complex mechanism involving, besides isomerization, even hydrogenation and dehydrogenation processes. Noticeably, new insights into the title reaction were also provided by the proposed approach.