Volumen II - SAM

El cálculo de la energía de adsorción para el sistema Ni-Ce0,75Zr0,25O2(111), indica que el Ni se adsorbe sobre
esa superficie ocupando preferentemente un sitio puente entre dos átomos de oxígeno. La ubicación entre dos
iones oxígeno primeros vecinos de Zr es la más favorable, seguida por una posición similar entre dos átomos
de oxígeno primeros vecinos de un catión Ce. Nuestros cálculos indican además que el Ni se adsorbe
débilmente on-top de los iones oxígeno vecinos al Zr. En cambio, el Ni no se adsorbe sobre un catión Ce
superficial.
AGRADECIMIENTOS
Agradecemos a la Universidad de Buenos Aires - UBACyT I411, Universidad Nacional del Sur, CONICET
y ANPCyT-PICT 560/2007 por el apoyo económico recibido para realizar este trabajo.
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