Ab Initio investigation of the interaction of H2 with lithium exchanged low-silica chabazites
The interaction of molecular hydrogen with the polarizing centers of lithiumexchanged chabazites with low Si/Al ratio (CHA-5/1 and CHA-3/1) was theoretically studied within a periodic approach at the B3LYP level of theory. The cation site preferences in both zeolites were determined and the H2 inter...
| Main Authors: | , , , , |
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| Other Authors: | |
| Format: | Conference Paper |
| Published: |
IOP
2008
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| Online Access: | http://hdl.handle.net/20.500.11937/44292 |
| _version_ | 1848756959049678848 |
|---|---|
| author | Civalleri, B. Torres, F. Demichelis, Raffaella Terentyev, A. Ugliengo, P. |
| author2 | Unknown |
| author_facet | Unknown Civalleri, B. Torres, F. Demichelis, Raffaella Terentyev, A. Ugliengo, P. |
| author_sort | Civalleri, B. |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | The interaction of molecular hydrogen with the polarizing centers of lithiumexchanged chabazites with low Si/Al ratio (CHA-5/1 and CHA-3/1) was theoretically studied within a periodic approach at the B3LYP level of theory. The cation site preferences in both zeolites were determined and the H2 interaction was then studied by adding a molecule in the proximity of the different polarizing centers. The energetic features of the H2-Li2CHA-5/1 complex were also refined by using a cluster model cut out from the periodic structure in which the contribution of the dispersive forces to the interaction (absent at the B3LYP level of theory) were estimated at the MP2 level by means of an ONIOM2-like approach. Overall results show that the position of the polarizing center in the structure and its stability in the site is crucial for determining the sorption capacity of the zeolite. Lithium exchanged low-silica zeolites are shown to be only effective for hydrogen storage when the Al loading is at least 3:1. However, the highest predicted enthalpy of adsorption is around 10 kJ/mol and this indicates that they are far from fulfilling the conditions for practical applications |
| first_indexed | 2025-11-14T09:20:29Z |
| format | Conference Paper |
| id | curtin-20.500.11937-44292 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| last_indexed | 2025-11-14T09:20:29Z |
| publishDate | 2008 |
| publisher | IOP |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-442922017-02-28T01:48:19Z Ab Initio investigation of the interaction of H2 with lithium exchanged low-silica chabazites Civalleri, B. Torres, F. Demichelis, Raffaella Terentyev, A. Ugliengo, P. Unknown The interaction of molecular hydrogen with the polarizing centers of lithiumexchanged chabazites with low Si/Al ratio (CHA-5/1 and CHA-3/1) was theoretically studied within a periodic approach at the B3LYP level of theory. The cation site preferences in both zeolites were determined and the H2 interaction was then studied by adding a molecule in the proximity of the different polarizing centers. The energetic features of the H2-Li2CHA-5/1 complex were also refined by using a cluster model cut out from the periodic structure in which the contribution of the dispersive forces to the interaction (absent at the B3LYP level of theory) were estimated at the MP2 level by means of an ONIOM2-like approach. Overall results show that the position of the polarizing center in the structure and its stability in the site is crucial for determining the sorption capacity of the zeolite. Lithium exchanged low-silica zeolites are shown to be only effective for hydrogen storage when the Al loading is at least 3:1. However, the highest predicted enthalpy of adsorption is around 10 kJ/mol and this indicates that they are far from fulfilling the conditions for practical applications 2008 Conference Paper http://hdl.handle.net/20.500.11937/44292 IOP restricted |
| spellingShingle | Civalleri, B. Torres, F. Demichelis, Raffaella Terentyev, A. Ugliengo, P. Ab Initio investigation of the interaction of H2 with lithium exchanged low-silica chabazites |
| title | Ab Initio investigation of the interaction of H2 with lithium exchanged low-silica chabazites |
| title_full | Ab Initio investigation of the interaction of H2 with lithium exchanged low-silica chabazites |
| title_fullStr | Ab Initio investigation of the interaction of H2 with lithium exchanged low-silica chabazites |
| title_full_unstemmed | Ab Initio investigation of the interaction of H2 with lithium exchanged low-silica chabazites |
| title_short | Ab Initio investigation of the interaction of H2 with lithium exchanged low-silica chabazites |
| title_sort | ab initio investigation of the interaction of h2 with lithium exchanged low-silica chabazites |
| url | http://hdl.handle.net/20.500.11937/44292 |