The DOI matches its Crossref record; 1 of the 1 references it cites were found in a registry or an index.
Flexible Aluminum Coordination in Alumino−Silicates. Structure of Zeolite H−USY and Amorphous Silica−Alumina
Abstract
The aluminum coordination in amorphous silica−alumina with different aluminum concentrations as well as in pure γ-Al 2 O 3 has been studied by means of 27 Al (MQ) MAS NMR spectroscopy. The effect of ammonia adsorption at 120 °C has been studied and compared with that on zeolite H−USY, as well as with zeolites with different topologies. As for protonic zeolites, part of the octahedral aluminum reversibly changed to tetrahedrally coordinated upon ammonia adsorption on amorphous silica−alumina. The distinction between flexible aluminum coordination in zeolites and silica−alumina was possibly based on the quadrupolar parameters. Ammonia adsorption on pure γ-Al 2 O 3 did not influence the aluminum coordination. A parallel between the structure of zeolite USY and that of amorphous silica−alumina was made on the basis of the results of 27 Al MQ MAS NMR spectroscopy. A partial conversion from octahedral to tetrahedral coordination upon ammonia adsorption was observed for zeolite H−USY. Most of the flexible aluminum species belongs to an amorphous silica−alumina phase, formed during the ultrastabilization process from the reaction between the extracted silicon and aluminum.
Overview
The claims and statistics of this paper haven’t been checked yet.
Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.
Integrity signals
Registry
Cites
Statistics
Verification
Claims the paper makes
The claims and statistics of this paper haven’t been checked yet.
Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.
Self-check
Percentages, sums and reported differences re-computed from the paper’s own numbers.
The self-check needs the paper’s full text.
Citations
Cites
Principles of Nuclear Magnetic Resonance in One and Two Dimensions
Ernst, R. R., Bodenhausen, G., & Wokaun, A. (1990) · doi:10.1093/oso/9780198556473.001.0001 · Cited by 1,418
Metadata
- Authors
- Omegna, A., van Bokhoven, J. A., & Prins, R.
- Venue
- The Journal of Physical Chemistry B
- Publisher
- American Chemical Society (ACS)
- Published
- 2003-08-01
- Volume
- 107
- Issue
- 34
- Pages
- 8854-8860
- ISSN
- 1520-5207 (ISSN-L)
- 1520-6106
- OpenAlex
- W2053630225
- Cited by
- 165
- References
- 1
- FWCI
- 5.52
- Type
- journal article
- Language
- en
- Open access
- closed
About these checks
Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.
Statistics and arithmetic are recomputed, not judged.
Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.
What counts as a claim ›How we measure confidence ›How we check this ›
Are you an author, or do you see a problem with this page? Request a review
How to cite
Cite CoChat for the checks on this page, and the paper for its own findings.
- This page
- CoChat. (2026). Citation check: Flexible Aluminum Coordination in Alumino−Silicates. Structure of Zeolite H−USY and Amorphous Silica−Alumina. https://app.cochat.ai/papers/10.1021/jp030094+
- The paper
- Omegna, A., van Bokhoven, J. A., & Prins, R. (2003). Flexible Aluminum Coordination in Alumino−Silicates. Structure of Zeolite H−USY and Amorphous Silica−Alumina. The Journal of Physical Chemistry B. https://doi.org/10.1021/jp030094%2B
Data sources
Bibliographic data: Semantic Scholar, OpenAlex, Crossref.
Contains information from the Semantic Scholar Academic Graph Datasets, made available under the ODC Attribution License (ODC-BY 1.0).
Semantic Scholar’s data is described in: Kinney, R., et al. (2023). The Semantic Scholar Open Data Platform. arXiv:2301.10140.
