Hydrogen adsorption on graphite (0001) surface: a combined spectroscopy-density-functional-theory study.

J Chem Phys

Physique des Interactions Ioniques et Moléculaires, Université de Provence and Centre National de la Recherche Scientifique, Unité Mixte de Recherche (CNRS-UMR) 6633, Campus de Saint Jérôme Service 242, France.

Published: September 2005

The adsorption of H/D atoms on the graphite (0001) surface is investigated by means of both high-resolution electron-energy loss spectroscopy (HREELS) and periodic first-principle density-functional theory. The two methods converge towards two modes of adsorption: adsorption in clusters of about four hydrogen atoms and adsorption in pairs of atoms on contiguous carbon sites. The desorption energies estimated from the calculated dissociation energies range from 8 to 185 kJ mol(-1) leading to an estimated surface coverage at saturations of 30-44 at. %. These results are compared with previous thermal desorption spectroscopy results. New HREEL signal assignments are proposed based on quantum calculations.

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http://dx.doi.org/10.1063/1.2043008DOI Listing

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