Stereodynamics of NO dissociative adsorption on Si(111)-(77) surface

Hashinokuchi, Michihiro*; Ito, Hironori*; Teraoka, Yuden; Moritani, Kosuke*; Okada, Michio*; Kasai, Toshio*

We have studied molecular-orientation effects for the dissociative adsorption of NO on Si(111)-77 surface using an oriented-molecular-beam apparatus designed efficient for X-ray photoelectron spectroscopy. The state-selected NO molecular beam with translational energy of 58 meV impinges on the Si surface of 400 K and adsorbed sites of oxygen and nitrogen on the surface have been analyzed by XPS as O1s and N1s photoelectron peaks. The O1s peak revealed that the yield of dissociatively-adsorbed O atoms for the N-end collision was larger than that for the O-end collision, and that for randomly-oriented NO gave the middle value of the two. The same steric preference was observed for the N1s peak. We would thus conclude that the N-end collision is more reactive than the O-end one.