Nitrogen recombination dynamics at Cu(111): Rotational energy release and product angular distributions
| Autor: | Andrew Hodgson, M.J. Murphy, J. F. Skelly |
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| Rok vydání: | 1998 |
| Předmět: | |
| Zdroj: | The Journal of Chemical Physics. 109:3619-3628 |
| ISSN: | 1089-7690 0021-9606 |
| DOI: | 10.1063/1.476959 |
| Popis: | Nitrogen atoms adsorbed on Cu(111) desorb thermally from an ordered Cu(100)−c(2×2)N phase in a sharp, zero order desorption feature near 700 K with an activation barrier of 143 kJ mol−1. Detailed N2 product rovibrational state distributions have been measured following recombinative desorption from a 700 K Cu(111) surface exposed to a N atom beam, with an equilibrium N coverage θN⩽10−2 ML. Although desorbing N2 is translationally and vibrationally hot, with a vibrational temperature of 5100 K and 4.2 eV of translational excitation perpendicular to the surface, rotation is excited with a temperature of just 910(±50) K for the vibrational ground state and 840(±250) K for (v=1). The energy released during recombinative desorption channels effectively into translational and vibrational motion, but not into rotational excitation. The angular distribution of recombinatively desorbed N2 is sharply peaked along the surface normal, P(θ)=cos(28±1) θ, indicating a mean energy release of 0.28 eV into translation para... |
| Databáze: | OpenAIRE |
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