uu.seUppsala University Publications
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Electronic structure of the CeO2(1 1 0) surface oxygen vacancy
Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Structural Chemistry.
Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Structural Chemistry.
Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Structural Chemistry.
2005 (English)In: Surface Science, ISSN 0039-6028, E-ISSN 1879-2758, Vol. 599, no 1-3, 173-186 p.Article in journal (Refereed) Published
Abstract [en]

The oxygen vacancy formation on the CeO2(1 1 0) surface has been studied by ab initio electronic structure calculations. Embedded-cluster calculations with explicit treatment of the electron correlation from Møller–Plesset perturbation theory (MP2) provide an alternative description of the surface O vacancy compared to previously reported periodic density functional theory (DFT) calculations. The electronic structure at the MP2 level shows a complete localization of the excess electrons on the two surface Ce ions neighboring the vacancy, contrary to the delocalized description seen in the periodic DFT calculations for the CeO2(1 1 0) surface (but more in line with DFT+U results recently reported for the partially reduced CeO2 bulk and (0 0 1)-surface). Our calculations predict a vacancy formation energy (3.1–3.3 eV at the MP2 level including basis set superposition error (BSSE) correction) and a geometric structure in qualitative agreement with the periodic DFT results, where the surface O ion next to the vacancy assumes a bridging position between the reduced Ce ions.

Place, publisher, year, edition, pages
2005. Vol. 599, no 1-3, 173-186 p.
Keyword [en]
Ab initio calculations, Vacancy formation, Ceria, Surface defect
National Category
Inorganic Chemistry
Identifiers
URN: urn:nbn:se:uu:diva-21786DOI: 10.1016/j.susc.2005.09.045OAI: oai:DiVA.org:uu-21786DiVA: diva2:49559
Available from: 2007-01-04 Created: 2007-01-04 Last updated: 2017-12-07Bibliographically approved
In thesis
1. Combined Molecular Dynamics and Embedded-Cluster Calculations in Metal Oxide Surface Chemistry
Open this publication in new window or tab >>Combined Molecular Dynamics and Embedded-Cluster Calculations in Metal Oxide Surface Chemistry
2005 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

The development and improvement of the functionality of metal oxides in heterogeneous catalysis and other surface chemical processes can greatly benefit from an atomic-level understanding of the surface chemistry. Atomistic calculations such as quantum mechanical (QM) calculations and molecular dynamics (MD) simulations can provide highly detailed information about the atomic and electronic structure, and constitute valuable complements to experimental surface science techniques.

In this thesis, an embedded-cluster approach for quantum mechanical calculations has been developed to model the surface chemistry of metal oxides. In particular, CO adsorption on the MgO(001) and CeO2(110) surfaces as well as O vacancy formation at the CeO2(110) surface have been investigated. The cluster model has been thoroughly tested by comparison with electronic structure calculations for the periodic slab model.

The chemical implications of distorted surface structures arising from the surface dynamics have been investigated by combining the QM embedded-cluster calculations with force-field based MD simulations. Here QM embedded-cluster calculations were performed using surface structures sampled from the MD simulations.

This combined MD+QM embedded-cluster procedure was applied to the CO adsorption on MgO(001) at 50 K and the O vacancy formation on CeO2(110) at 300 K. Significant thermal variations of the CO adsorption energy and the O vacancy formation energy were observed. It was found that these variations could be estimated using the force field of the MD simulation as an interaction model. With this approach, the QM results were extrapolated to higher temperature and doped systems.

Place, publisher, year, edition, pages
Uppsala: Acta Universitatis Upsaliensis, 2005. 52 p.
Series
Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology, ISSN 1651-6214 ; 130
Keyword
Inorganic chemistry, embedded-cluster, ab initio, molecular dynamics, metal oxide, ceria, magnesium oxide, adsorption, surface defect, Oorganisk kemi
National Category
Inorganic Chemistry
Identifiers
urn:nbn:se:uu:diva-6227 (URN)91-554-6422-X (ISBN)
Public defence
2006-01-19, Room 2001, Ångströmlaboratoriet, Lägerhyddsvägen 1, Uppsala, 10:15
Opponent
Supervisors
Available from: 2005-12-23 Created: 2005-12-23 Last updated: 2013-09-18Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full text

Authority records BETA

Herschend, BjörnHermansson, Kersti

Search in DiVA

By author/editor
Herschend, BjörnHermansson, Kersti
By organisation
Structural Chemistry
In the same journal
Surface Science
Inorganic Chemistry

Search outside of DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetric score

doi
urn-nbn
Total: 842 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf