Effect of the Thickness of a Nickel Film on the W(110) Surface on the Character of the Adsorption of Nitric Oxide Molecules

Abstract

The adsorption of nitric oxide NO molecules on the surface of structurally ordered 1, 2, and 3 monolayer thick nickel films deposited on the W(110) surface has been studied by the method of reflection-absorption infrared spectroscopy. The structure of the nickel films of all examined thicknesses correspond to that of the Ni(111) crystal. The IR spectra of the NO molecules adsorbed on a 3-monolayer Ni film correspond to those of NO on the bulk Ni(111) crystal. For thinner films, more pronounced differences are observed for the monolayer film. This is due to the additional effect of the underlying W(110) substrate on the intramolecular NO bond and/or distortion of the (111) structure of the monolayer Ni film compared to bulk Ni(111) because of the potential substrate relief and the change of the adsorption geometry and the electron state of the NO molecules.