Water Adsorption at Pairs of Proximate Bronsted Acid Sites in Zeolites.

ABSTRACT: We model water adsorption at pairs of proximate Brønsted acid sites (BASs) in zeolites H-MFI, H-FAU, and H-CHA. We use machine-learning potentials to explore the potential energy surface, combined with quantum mechanical methods for chemically accurate energies of selected structures. We identify BAS pairs that adsorb water cooperatively, forming an H-bonded chain that connects the two BASs and provides additional stabilization. The formation of such a water bridge requires at least two molecules, making the adsorption of the second water molecule stronger than the first, e.g., by 20 and 44 kJ mol^-1 for an Al9-Al10 and an Al4-Al6 pair, respectively, in H-MFI, and by 11 kJ mol^-1 for H-FAU. The magnitude of this extra-stabilization depends on the relative alignment of t

SUBMITTER: Windeck H 

PROVIDER: S-EPMC12862806 | biostudies-literature | 2026 Jan

REPOSITORIES: biostudies-literature