Mixed Molecular and Dissociative Water Adsorption on MgO[100]
نویسنده
چکیده
First principles molecular dynamics (MD) simulations, of water adsorption on the MgOf100g surface, was performed to determine the molecular structure and chemical nature of the adsorbed water at varying coverage. Dissociative adsorption was stabilized by hydrogen bond donation from neighboring water molecules. The dissociation barrier had a strong dependence on coverage. Spontaneous dissociation was observed in picosecond MD simulations above 1y2 monolayer (ML) coverage. Ordered structures with cf3 3 2g symmetry were examined at 2y3 and 1 ML coverage. The ordered cf3 3 2g phase consisted of a mixture of dissociated and molecular adsorbed molecules. [S0031-9007(99)09103-6]
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