Dynamics of the oxygen molecules scattered from the graphite (0001) surface and comparison with experimental data

Abstract

A quasiclassical trajectory dynamics study of molecular oxygen colliding over a free of defects and clean graphite (0001) surface has been performed with a recently published density functional theory based flexible periodic London-Eyring-Polanyi-Sato potential energy surface (PES). Although the PES was mainly constructed for describing accurately the recombination of atomic oxygen over an O-preadsorbed surface, here we show that this PES is also reliable to study the scattering of O 2 over a graphite surface. Thus, several initial conditions have been explored: collision energies (0.2 eV ≥ E col ≥ 1.2 eV), incident angles (θ v = 0, 45°), surface temperatures (100 K ≥ T surf ≥ 900 K), and some rovibrational O 2 levels (v = 0, 1, 2 and j = 1, 17, 25). The calculated polar scattering angular distributions are in good agreement with the experimental ones in a wide range of explored conditions. Moreover, the comparison with hyperthermal experimental data, which was unclear in a previous work, has been finally clarified. The effect of O 2 (v, j) internal state on the scattering is very small. © 2012 American Chemical Society.