Structural and electronic features of a Broensted acid site in H-ZSM-5
- Lawrence Berkeley Lab., CA (United States) Univ. of California, Berkeley (United States)
The authors report the results of local density functional theory calculations on a Broensted acid site of the zeolite H-ZSM-5. They have investigated the structural and electronic properties of the site. Comparison is made between their results and existing experimental data. It is shown that structural relaxation around an acid site must be performed to obtain accurate energetics for substitution of aluminum into the zeolite framework. The effects of cluster termination are studied by comparing results obtained for both isolated clusters and clusters embedded in a Madelung field generated by the zeolite framework. The properties of the electron density distribution in the region around an acidic proton indicate that the acidic moiety may be characterized as a rather soft acid. 47 refs., 5 figs., 4 tabs.
- OSTI ID:
- 6077563
- Journal Information:
- Journal of Physical Chemistry; (United States), Vol. 97:25; ISSN 0022-3654
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
ZEOLITES
ELECTRONIC STRUCTURE
ALUMINIUM IONS
EXPERIMENTAL DATA
MATHEMATICAL MODELS
MOLECULAR ORBITAL METHOD
QUANTUM MECHANICS
CALCULATION METHODS
CHARGED PARTICLES
DATA
INFORMATION
INORGANIC ION EXCHANGERS
ION EXCHANGE MATERIALS
IONS
MATERIALS
MECHANICS
MINERALS
NUMERICAL DATA
SILICATE MINERALS
360204* - Ceramics
Cermets
& Refractories- Physical Properties
400201 - Chemical & Physicochemical Properties