Molecular Mechanism of Ethylene Epoxidation on Silver: State of the Problem and Theoretical Approaches Full article
Conference |
NATO Advanced Study Institute on Computational Materials Science 06-22 Sep 2001 , Il Ciocco |
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Source | Computational materials science : Proceedings of the NATO Advanced Study Institute on Computational Materials Science, 6-22 September 2001, Il Ciocco, Italy Compilation, IOS Press. Washington, DC.2003. 428 c. ISBN 9781586033354. |
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Journal |
NATO Science Series, Series III: Computer and Systems Sciences
ISSN: 1387-6694 |
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Output data | Year: 2003, Volume: 187, Pages: 334-358 Pages count : 25 | ||
Tags | IN-SITU RAMAN; EFFECTIVE CORE POTENTIALS; AB-INITIO; POLYCRYSTALLINE SILVER; HIGH-TEMPERATURE; OXYGEN STATES; SELECTIVE OXIDATION; SINGLE-CRYSTAL; ATOMIC OXYGEN; SURFACE | ||
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Abstract:
A new concept of the oxygen species epoxiclizing ethylene on silver is presented. The epoxiclizing oxygen is formed on the defects of the partially oxidized metal silver surface. Oxygen saturates the bulk of silver at high temperature (T > 500 K) and pressure of the reaction medium, and the whole subsurface layer becomes highly defective. We consider a cluster model of the defect structure surface AS(V), including a silver atom vacancy and the subsurface oxygen atoms Calculations were performed in the framework of DFT approach. It was shown that the subsurface oxygen atoms tend towards self-association and formation of quasi- molecular oxygen structures inside of the vacancy space. Adsorption of the oxygen atom on site AS(V) also provides stabilization of the Surface quasi-molecular ("ozonide") form, AS(V) + 0 --> AS(d)-O. We discuss the experimental XPS, UPS, IR, and Raman spectroscopy providing evidence in favor of stabilization of the quasi-molecular oxygen forms on the reactive silver surface. A theoretical interpretation of the experimental data is based on the proposed model of associative oxygen forms.
Cite:
Zhidomirov G.M.
, Avdeev V.I.
, Boronin A.I.
Molecular Mechanism of Ethylene Epoxidation on Silver: State of the Problem and Theoretical Approaches
In compilation Computational materials science : Proceedings of the NATO Advanced Study Institute on Computational Materials Science, 6-22 September 2001, Il Ciocco, Italy. – IOS Press., 2003. – C.334-358. – ISBN 9781586033354. WOS
Molecular Mechanism of Ethylene Epoxidation on Silver: State of the Problem and Theoretical Approaches
In compilation Computational materials science : Proceedings of the NATO Advanced Study Institute on Computational Materials Science, 6-22 September 2001, Il Ciocco, Italy. – IOS Press., 2003. – C.334-358. – ISBN 9781586033354. WOS
Identifiers:
Web of science | WOS:000189488000017 |
Citing:
DB | Citing |
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Web of science | 1 |