Weak molecular chemisorption of  N2/Pt(111)

The ordering in a higher-order-commensurate monolayer solid of Pt(111)-(3 × 3)-4 N₂, which has coexisting physisorbed and weakly chemisorbed N₂ species, is analyzed with model calculations. Density functional theory calculations are also used to evaluate properties of chemisorbed N₂ in a (2 × 2) unit cell on Pt(111). The relation of these results to the orientational ordering of N₂ on other metal surfaces is discussed.