Experimental kinetic studies deal with complex reaction networks, whereas computational studies can provide energy barriers, reaction energies and pre-exponentials for individual reaction and adsorption steps. If made with sufficient, i.e. chemical, accuracy, computational predictions are very useful to check critical steps in microkinetic models. The availability rigorous methods made it possible to revise the well-established “Lunsford” mechanism for the oxidative coupling of methane on Li-doped MgO and to predict an alternative one that stimulated new experiments. Our hybrid high level QM:low level QM method1 has been demonstrated to yield chemical accuracy (4 kJ/mol for energies and one order of magnitude for rate constants) for the methylation of ethene, propene and butene in H-ZSM-5. We demonstrate the importance of accurate predictions for the heat of adsorption and intrinsic barriers for understanding hydrocarbon activation by acidic zeolites, in particular proton exchange and cracking of alkanes as well as the formation of p-complexes, alkoxides, and carbenium ions from alkenes.

Ab initio predictions for elementary adsorption and reaction steps in heterogeneous catalysis

ACS Spring 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.