Classical dynamics study of atomic oxygen over graphite (0001) with new interpolated and analytical potential energy surfaces

Two adiabatic potential energy surfaces (PESs) based on density functional theory data are constructed for the interaction of atomic oxygen with graphite (0 0 0 1) surface: an analytical FPLEPS PES and an interpolated Modified Shepard one. A classical trajectory study has been performed for the two...

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Detalles Bibliográficos
Autores: Morón Tejero, Víctor, Martin-Gondre, Ludovic, Crespos, Cédric, Larregaray, Pascal, Gamallo Belmonte, Pablo, Sayós Ortega, Ramón
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2012
País:España
Institución:Varias* (Consorci de Biblioteques Universitáries de Catalunya, Centre de Serveis Científics i Acadèmics de Catalunya)
Repositorio:Recercat. Dipósit de la Recerca de Catalunya
OAI Identifier:oai:recercat.cat:2445/163106
Acceso en línea:https://hdl.handle.net/2445/163106
Access Level:acceso abierto
Palabra clave:Química quàntica
Dissociació (Química)
Adsorció
Teoria del funcional de densitat
Quantum chemistry
Dissociation
Adsorption
Density functionals
Descripción
Sumario:Two adiabatic potential energy surfaces (PESs) based on density functional theory data are constructed for the interaction of atomic oxygen with graphite (0 0 0 1) surface: an analytical FPLEPS PES and an interpolated Modified Shepard one. A classical trajectory study has been performed for the two PESs for different initial conditions: collision energy (0.1 ⩽ Ecol ⩽ 1.3 eV), surface temperature (100 ⩽ Tsurf ⩽ 900 K) and two incident angles (θv = 0°, 45°), and also for thermal conditions (T = TOxygen = Tsurf = 300-1500 K). In addition, hyperthermal experimental conditions corresponding to a hot atom distribution (〈Ecol〉 = 5.2 eV) were also considered. All the properties studied for the two PESs were in close agreement in almost the major part of the explored conditions, although some differences were obtained for low Ecol due to the presence of a physisorption minimum in the MS PES that was not included into the FPLEPS one. The adsorption process occurs mainly over bridge sites. Adsorption probabilities are lower than reflection ones in practically all the conditions explored and increase quickly with Ecol until a maximum and then decrease smoothly. Polar scattering angle distributions present a peak centred around the specular angle position and broaden when increasing Ecol or Tsurf. A good agreement respect this peak position was found in comparison with the experimental hyperthermal data. The transfer of energy is mainly from the atom to the surface and increases when initial collision energy does.