Ab initio study of the bridging hydroxyl acidity and stability in the 12-membered ring of zeolites

Frederik Tielens (1) , W Langenaeker , P Geerlings

1 VUB - Vrije Universiteit Brussel

The influence of Al/Si substitutions on the stability and acidic characteristics of a zeolite system is investigated. The 12-membered ring present in a number of zeolites was chosen as a realistic model system for this purpose. The stability of this system upon different double Al/Si substitutions was investigated in order to find evidence for both Lowenstein's and Dempsey's rules. It was found that both rules hold for the chosen model system. The acidity of the bridging hydroxyls was studied using the calculated deprotonation energy and the Mulliken and ChelpG electronic populations on the H-atom and on the O atom in the conjugated base. (C) 2000 Elsevier Science B.V. All rights reserved.

Domaines: Matériaux

Frederik Tielens, W Langenaeker, P Geerlings. Ab initio study of the bridging hydroxyl acidity and stability in the 12-membered ring of zeolites. Journal of Molecular Structure: THEOCHEM, 2000, 496, pp.153-162. ⟨10.1016/S0166-1280(99)00178-5⟩. ⟨hal-01361391⟩