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Updated: Jun 26, 2026

Quantitative Atomic-Site Analysis of Functional Dopants/Point Defects in Crystalline Materials by Electron-Channeling-Enhanced Microanalysis
Published on: May 10, 2021
Exploring the reactivity of framework vanadium, niobium, and tantalum sites in zeolitic materials using DFT
1Laboratoire de Réactivité de Surface, UPMC Université Paris 06, UMR 7609, Tour 54-55, 2ème étage-Casier 178, 4, Place Jussieu, F-75005 Paris, France. frederik.tielens@upmc.fr
Abstract:
The acid-base properties of zeolites with group 5 transition metal framework sites are investigated, and a first step into the understanding of their acid/base and redox properties is undertaken using DFT reactivity descriptors. It is evidenced, using sodalite as model system, that zeolites with vanadium framework sites are more nucleophilic than zeolites with niobium and tantalum framework sites. It is predicted that the formation of carbonates would be favorable in zeolites with Ta framework sites compared with V framework sites, whereas the basicity of the bridging oxygens is predicted to interact preferentially with a soft nucleophile. In this context, the poisoning of the deNO(x) catalysts in the presence of SO2 is discussed.
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