ADSORPTION-INDUCED BENDING OF A TRIATOMIC MOLECULE - NEAR-EDGE X-RAY-ABSORPTION FINE-STRUCTURE SPECTROSCOPY INVESTIGATION OF N2O ADSORBED ON DIFFERENT NI(111) SURFACES

A monolayer of N2O/Ni(111), a submonolayer species, and a monolayer of N2O/Ni(111) + O p[2 x 2] were studied using near-edge x-ray absorptio n fine-structure spectroscopy. From the polarization dependence we der ive bent N2O molecules for the monolayer species whereas the two other species remain linear upon adsorption. Using the X alpha-scattered-wa ve method the polarization dependence of the three pi resonances was calculated explicitly for linear and bent N2O molecules. The calculati ons reproduced the experimental results quantitatively, yielding a bon d angle of 165 degrees for the monolayer species.