The adsorption of nitrogen dioxide on the Ag(110) surface and formation of a surface nitrate

The adsorption of NO2 on the Ag(110) surface has been characterized by temperature programmed reaction spectroscopy and high resolution electron energy loss spectroscopy. At 95 K the NO2 is dimerized to N2O4 in a multilayer and a distinct molecular layer, both of which desorb below 200 K. The first adsorption layer contains chemisorbed NO2 and NO3, the latter formed by a reaction between NO2 and its decomposition products. Part of the NO2 is molecularly chemisorbed via the oxygen atoms with a proposed symmetric bidentate geometry, desorbing at 270 K. Nitrogen dioxide also undergoes partial dissociation to nitrogen and oxygen adatoms. An NO3 species is formed by the reaction of NO2 with the oxygen adatoms produced from the partial dissociation of NO2. The NO3 is attached to the surface via one oxygen atom and has C2v symmetry; it decomposes below 500 K. The geometry of both the chemisorbed NO2 and NO3 have analogues among inorganic metal complexes.