Brønsted Acid Sites in HSAPO-34 and Chabazite: An Ab Initio Structural Study

Yannick Jeanvoine; János G. Ángyán; Kresse Georg; Jürgen Häfner

doi:10.1021/jp980341n

Brønsted Acid Sites in HSAPO-34 and Chabazite: An Ab Initio Structural Study

The Journal of Physical Chemistry B 102(29): 5573-5580

Article 1998 English

Abstract

1 min read

The structure of Brønsted acid sites and the effects of the Al → Si and Si → P substitution in chabazite and AlPO4-34 frameworks, respectively, have been studied by ab initio plane-wave calculations on periodic models. Geometry distortions remain well localized to the nearest neighborhood of the Brønsted acid site. The Si−O(H) and Al−O(H) distances of the common Si−O(H)−Al moiety are significantly different in the two kinds of materials. Calculated OH stretching frequencies of acidic protons, which could be assigned to the low- and high-frequency OH bands, in agreement with experimental infrared spectra of H-SSZ-13 (high silica chabazite) and HSAPO-34, correlate with OH bond lengths and Si−O(H)−Al angles.

Brønsted Acid Sites in HSAPO-34 and Chabazite: An Ab Initio Structural Study

Abstract

Discussion(0)

Related publications

On the Nature of Water Interacting with Brønsted Acidic Sites. Ab Initio Molecular Dynamics Study of Hydrated HSAPO-34

The role of the electrostatic potential, electric field and electric field gradient on the acidity of AFI and CHA zeotypes

Structural incorporation of nitrogen into zeolites, and alpos: ab initio molecular orbital calculations on stability and basicity

Density Functional Theory Calculations of the Effects of Local Composition and Defect Structure on the Proton Affinity of H−ZSM-5

A molecular dynamics study of N–A–S–H gel with various Si/Al ratios

Related publications

Article1998
On the Nature of Water Interacting with Brønsted Acidic Sites. Ab Initio Molecular Dynamics Study of Hydrated HSAPO-34
Article1998

Article2000
The role of the electrostatic potential, electric field and electric field gradient on the acidity of AFI and CHA zeotypes
Article2000

Article1998
Structural incorporation of nitrogen into zeolites, and alpos: ab initio molecular orbital calculations on stability and basicity
Article1998

Article1997
Density Functional Theory Calculations of the Effects of Local Composition and Defect Structure on the Proton Affinity of H−ZSM-5
Article1997

Article2022
A molecular dynamics study of N–A–S–H gel with various Si/Al ratios
Article2022