“…1,2 Prominent examples are the Haber-Bosch process for ammonia synthesis, 3 the cracking of long-chain hydrocarbons in the petroleum industry, 4 and the oxidation of sulphur dioxide to sulphur trioxide finally yielding sulphuric acid. 5,6 The improvement of such catalytic systems crucially depends on a detailed understanding of the reaction mechanisms at the atomic scale that are governed by the potential energy surface (PES), which is a high-dimensional function providing the energy and forces for any given atomic configuration. Thus, the PES determines the dynamics of the reactants at the surface, the making and breaking of bonds and, finally, product formation.…”