Density functional theory study of NO on the Rh(1 0 0) surface

Density functional theory has been used to perform a systematic study of the adsorption of NO on the Rh(1 0 0) surface. A detailed discussion about the structural configurations, work functions, and the frequency modes for all the adsorption sites at several coverages is given. NO has possibly two adsorption sites. NO is found to adsorb in bridge sites at all coverages. A highly inclined NO is present on the surface at low coverages, with a stability close to the NO adsorbed in bridge position. The activation barrier for tilting NO from the inclined to the bridge position is low. A discussion of partial density of states and charge density differences for the stable positions is given. The calculated intensity of the stretching vibration of NO adsorbed in bridge is much higher than the one corresponding to the stretching vibration of NO adsorbed in inclined position. At NO saturation coverage theory predicts various vibrational modes. A discussion about the way in which they might appear is given.