Adsorption of V on a hematite (0001) surface and its oxidation: Monolayer coverage
نویسندگان
چکیده
The adsorption of a monolayer of V on idealized Feand oxygen-terminated hematite (0001) surfaces and subsequent oxidation under atomic O adsorption are studied by density functional theory. Theoretical results are compared with X-ray surface standing wave and X-ray photoelectron spectroscopic measurements, and interpreted in the light of data on sub-monolayer coverages. Near-surface Fe reduction under V adsorption and accompanying structural relaxation are examined. These effects and subsequent response to oxidation, are found to be highly site specific. A full monolayer of oxygen leads to a V state and reoxidation of subsurface Fe to the trivalent state, seen in both theory and experiment. 2007 Elsevier B.V. All rights reserved.
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Adsorption of V on a hematite (0001) surface and its oxidation: Submonolayer coverage
The adsorption of submonolayer V on an idealized model hematite (0001) surface and subsequent oxidation under atomic O adsorption are studied by density functional theory. The preferred adsorption sites, adsorption energy and configuration changes due to V and O adsorption are investigated. It is found that in most cases V forms threefold bonds with surface O atoms, inducing a large geometry ch...
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