Chemical Dynamics Simulations and Scattering Experiments for O2 Collisions with Graphite

• DOI: 10.1021/acs.jpcc.8b02574
• Publication Date: 2018-06-21T18:17:11Z
• Authors: Moumita Majumder; K. D. Gibson; S. J. Sibener; William L. Hase
• Keywords: Physisorption

Energy transfer in collisions of O2 with a graphite surface was studied by chemical dynamics simulations. The simulations were performed for three collision energies Ei 2.1, 7.4, and 15 kcal/mol, the initial incident angle fixed at θi = 45°. Simulations each temperature Tsurf 300 K. For higher 1177 K, simulation only kcal/mol. following properties determined analyzed + collisions: (1) translational energy distributions scattered O2; (2) distribution final polar azimuthal (3) number bounces on before scattering. average transferred to that remaining translation, i.e., ⟨ΔEsurf⟩ ⟨Ef⟩, exhibit linear dependence energy. scattering, physisorption/desorption residence time decays exponentially, an increase decrease Ei. rate which decreases shows near-linear collisional 7.4 scattering from follows nearly quasi-trapping desorption process. However, lowest energy, it mostly conventional physisorption/desorption. all conditions considered experimentally, relationship between molecules found is excellent agreement experimental results. This validation precise outcomes important as indicates energy-transfer predictions this system can be reliably used assessing interfacial flow variety technological applications, including high-performance flight systems.