Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5441048 | Journal of Non-Crystalline Solids | 2017 | 5 Pages |
Abstract
The effect of Na+/K+ ion exchange on the distribution of the modifier ions and on their interaction with the oxygen atoms in the network is investigated in ternary Na,Mg- and Na,Ca- silicate glasses using 17O triple-quantum magic-angle-spinning nuclear magnetic resonance spectroscopy. The results indicate that the K+ ions preferentially exchange with the Na+ ions present in {Na,Ca}-NBO and {Na,Mg}-NBO environments, while the Na-NBO environment is not significantly affected. Remelting of the ion-exchanged glasses leads to a homogenization of the modifier ion distribution around the NBO sites. The dynamical site preference for the Na+/K+ ion exchange has far-reaching implications in our understanding of the alkali ion transport and more specifically of the mixed-alkali effect in silicate glasses.
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Physical Sciences and Engineering
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Authors
C. Ragoen, M.A.T. Marple, S. Sen, F. Boland, S. Godet,