English   español  
Please use this identifier to cite or link to this item: http://hdl.handle.net/10261/44251
logo share SHARE logo core CORE   Add this article to your Mendeley library MendeleyBASE

Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL | DATACITE
Exportar a otros formatos:


Water-induced surface reconstruction of oxygen (2×1) covered Ru(0001)

AuthorsCabrera-Sanfélix, Pepa ; Sánchez-Portal, Daniel ; Arnau, Andrés ; Salmerón, Miquel
Issue Date2010
PublisherAmerican Physical Society
CitationPhysical Review B 82(7): 075421 (2010)
AbstractLow-temperature scanning tunneling microscopy and density-functional theory (DFT) were used to study the adsorption of water on a Ru(0001) surface covered with half monolayer of oxygen. The oxygen atoms occupy hcp sites in an ordered structure with (2×1) periodicity. DFT predicts that water is weakly bound to the unmodified surface, 86 meV compared to the ∼200 meV water-water H bond. Instead, we found that water adsorption causes a shift of half of the oxygen atoms from hcp sites to fcc sites, creating a honeycomb structure where water molecules bind strongly to the exposed Ru atoms. The energy cost of reconstructing the oxygen overlayer, around 230 meV per displaced oxygen atom, is more than compensated by the larger adsorption energy of water on the newly exposed Ru atoms. Water forms hydrogen bonds with the fcc O atoms in a (4×2) superstructure due to alternating orientations of the molecules. Heating to 185 K results in the complete desorption of the water layer, leaving behind the oxygen-honeycomb structure, which is metastable relative to the original (2×1). This stable structure is not recovered until after heating to temperatures close to 260 K.
Description10 páginas, 14 figuras, 1 tabla.-- PACS number(s): 68.43.Bc, 68.37.Ef.-- et al.
Publisher version (URL)http://dx.doi.org/10.1103/PhysRevB.82.075421
Appears in Collections:(CFM) Artículos
Files in This Item:
File Description SizeFormat 
e075421.pdf1,41 MBAdobe PDFThumbnail
Show full item record
Review this work

Related articles:

WARNING: Items in Digital.CSIC are protected by copyright, with all rights reserved, unless otherwise indicated.