Surface self-diffusion of a Pt adatom on cuboctahedral and truncated decahedral clusters,size dependence |
| |
Authors: | J Y Yang W Y Hu and J F Tang |
| |
Institution: | (1) Department of Electrical and Computer Engineering, Portland State University, Portland, OR 97207-0751, USA |
| |
Abstract: | The self-diffusion of single Pt adatom on the surface of cuboctahedral and truncated decahedral clusters with 561–10 179 atoms
are studied
within the context of the many-body potentials obtained via the embedded atom method. The minimum energy diffusion path and
the corresponding
energy barrier for adatom diffusion on the cuboctahedral and truncated decahedral clusters surfaces are determined through
a combination of the
quenched molecular dynamics and the nudged elastic band method. The calculated energy barriers are consistent with the available
experimental
data. The dependence of energy barrier for adatom diffusion across the step edge on the cluster size is found. For the larger
cuboctahedral and
truncated decahedral clusters, the simulations show that the movement of the adatom is confined to a central region, and the
adatom may escape
from the center region only at elevated temperatures. In addition, we also find that the truncated decahedral structure is
more favorable over
the cuboctahedral structure for smaller clusters. The cluster growth experiments support our results. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|