Analysis of the heterogeneous recombination of oxygen atoms on aluminum oxide by methods of quantum mechanics and classical dynamics

• Published in: Fluid dynamics Vol. 45; no. 2; pp. 305 - 311
• Main Authors: Kovalev, V. L., Krupnov, A. A., Pogosbekyan, M. Yu, Sukhanov, L. P.
• Format: Journal Article
• Language: English
• Published: Dordrecht SP MAIK Nauka/Interperiodica 01-04-2010
• Subjects: Aluminum oxide; Atmosphere entry; Classical and Continuum Physics; Classical Mechanics; Coatings; Engineering Fluid Dynamics; Fluid- and Aerodynamics; Mathematical models; Molecular dynamics; Oxygen atoms; Physics; Physics and Astronomy; Reusable; Surface chemistry; heterogeneous catalytic processes; quantum mechanics; chemically reacting hypersonic flows; molecular dynamics
• ISSN: 0015-4628; 1573-8507
• DOI: 10.1134/S0015462810020158

On the basis of the density-functional theory, cluster models of the adsorption of oxygen atoms on aluminum oxide are constructed and the corresponding potential-energy surface is calculated. Quantum-mechanical calculations showed that it is necessary to take into account the angular dependence of the potential-energy surface and the relaxation of the surface monolayers. Using this surface in molecular dynamics calculations made it possible to obtain the probabilities of the heterogeneous recombination of oxygen atoms on the α-Al
2
O
3
surface, which are in good agreement with experimental data. The calculations performed substantially decrease the amount of experimental investigations necessary reliably to describe the heterogeneous catalysis on promising reusable heat shield coatings for analyzing heat transfer during spacecraft entry into the atmosphere.