Electron transfer processes on Ag and Au clusters supported on TiO{sub 2}(110) and cluster size effects
- Laboratoire des Collisions Atomiques et Moleculaires, Unite Mixte CNRS Universite UMR8625, bat 351, Universite Paris Sud, 91405 Orsay (France) and CEFIC, Departamento de Fisica, Universidade de Lisboa, 2829-516 Caparica (Portugal) and Laboratoire des Collisions Atomiques et Moleculaires, Unite Mixte CNRS Universite UMR8625, bat 351, Universite Paris Sud, 91405 Orsay (France)
The results of a detailed study of Li{sup +} neutralization in scattering on Ag and Au clusters and thin films supported on TiO{sub 2} are presented. A very efficient neutralization is observed on small clusters with a decrease for the smallest clusters. These results closely follow the size-effects observed in the reactivity of these systems. The energy dependence of the neutralization was studied for the larger clusters (>4 nm) and observed to be similar in trend to the one observed on films and bulk (111) crystals. A general discussion of possible reasons of the enhancement in neutralization is presented and these changes are then tentatively discussed in terms of progressive modifications in the electronic structure of clusters as a function of reduction in size and as it evolves from metallic-like to discretised states. The highest neutralization efficiency would appear to correspond to clusters sizes for which a metal to nonmetal transition occurs. The relative position of the Li level and the highest occupied molecular orbital in the molecular cluster can be expected to strongly affect the electron transfer processes, which in this case should be described in a molecular framework.
- OSTI ID:
- 20783305
- Journal Information:
- Journal of Chemical Physics, Vol. 124, Issue 22; Other Information: DOI: 10.1063/1.2205849; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-9606
- Country of Publication:
- United States
- Language:
- English
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