DFT Analysis of Propane Cyclization over Binuclear Ga-Clusters in Mordenite

Molecular and dissociative adsorption of propane on binuclear (Ga2O2)2+ cluster located at the cation positions of Ga-exchanged mordenite zeolite are modeled using DFT calculations via the isolated cluster approach. Relative energies of the dissociative intermediates show the most stable bidentate complexes, i.e., via both primary C atoms of propane to both Ga atoms. This structure really is the suitable precursor of cyclo-propane formation. The hypothesis of cyclo-propane intermediate was proposed by Derouane et al. to explain the 13C/12C exchange migration within propane molecules in Ga-exchanged zeolites.