Incoherent Inelastic Neutron Scattering Studies of Nanoconfined Water in Clinoptilolite and Heulandite Zeolites
| Autor: | Monika Hartl, Tina Maria Nenoff, Randall Timothy Cygan, Luke L. Daemen, Nathan W. Ockwig |
|---|---|
| Rok vydání: | 2008 |
| Předmět: |
Clinoptilolite
Chemistry Inorganic chemistry Charge density engineering.material Heulandite Alkali metal Electric charge Inelastic neutron scattering Surfaces Coatings and Films Electronic Optical and Magnetic Materials Ion General Energy Aluminosilicate Chemical physics engineering Physical and Theoretical Chemistry |
| Zdroj: | The Journal of Physical Chemistry C. 112:13629-13634 |
| ISSN: | 1932-7455 1932-7447 |
| DOI: | 10.1021/jp803770v |
| Popis: | In a continued effort studying the role of water in ion exchange processes of zeolites, a synthetic series of alkali and alkaline earth metal cation variants (Na+, K+, Rb+, Mg2+, and Ca2+) of the hydrated clinoptilolite (Si/Al ≈ 5) and heulandite (Si/Al ≈ 3.5) aluminosilicate zeolites is examined by incoherent inelastic neutron scattering (IINS). The low-frequency librational modes of water reveal the impact of nanoconfinement and framework charge within these isostructural aluminosilicate structures. The experimental IINS spectra are correlated with power spectra derived through molecular dynamics simulations. The impact of ion−zeolite, ion−water, and water−zeolite interactions on the hindered rotations (librations) of water molecules is explored as a function of Si/Al substitution, cation identity, and subnanometer confinement. The results indicate that electrostatic charge on the overall framework has a stronger influence than charge density of a given ion in the channel and that these effects become m... |
| Databáze: | OpenAIRE |
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