BARC/PUB/2004/0390

 
 

Tantalum-fullerene clusters: A first-principles study of static properties and dynamical behavior

 
     
 
Author(s)

Ramaniah, L. M.; Boero, M.; Laghate, M.
(SRS)

Source

Physical Review-B, 2004. Vol. 70 (3): pp. 035411.1-035411.14

ABSTRACT

The static structural properties and the relative stability of fullerene molecules decorated with one, two, and three Ta atoms at different exohedral sites are investigated via first-principles calculations. We find that the most stable clusters are likely to be those in which a Ta atom is at a site of high electron density, such as the hexagon-hexagon double bond of the fullerene molecule, and if the Ta atoms cluster together on the surface of the cage. Dynamical simulations of the C60Ta3 system are performed via Car-Parrinello molecular dynamics, and they show that the Ta atoms on the surface of the fullerene are affected by a rather high mobility, similar to the surface diffusion of a physisorbed species. Though a Ta dimer is formed at relatively low temperatures, the C60Ta3 cluster is dynamically stable up to a temperature of ~1000 K, ruling out purely thermal heating as a major factor responsible for any fragmentation process at least on time scales of a few picoseconds.

 
 
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