TY - JOUR
T1 - A Kinetic Monte Carlo Approach for Self-Diffusion of Pt Atom Clusters on a Pt(111) Surface
AU - R. Deák, Z. Néda & P. B. Barna
JO - Communications in Computational Physics
VL - 4
SP - 920
EP - 939
PY - 2011
DA - 2011/10
SN - 10
DO - http://doi.org/10.4208/cicp.130410.031210a
UR - https://global-sci.org/intro/article_detail/cicp/7469.html
KW - 
AB - <p style="text-align: justify;">A lattice Kinetic Monte Carlo (KMC) approach is considered to study the
statistical properties of the diffusion of Pt atom clusters on a Pt(111) surface. The interatomic
potential experienced by the diffusing atoms is calculated by the embedded
atom method and the hopping barrier for the allowed atomic movements are calculated
using the Nudged Elastic Band method. The diffusion coefficient is computed
for various cluster sizes and system temperatures. The obtained results are in agreement
with the ones obtained in previous experimental and theoretical works. A simple
scaling argument is proposed for the size dependence of the diffusion coefficient&#39;s prefactor.
A detailed statistical analysis of the event by event KMC dynamics reveals two
important and co-existing mechanisms for the diffusion of the cluster&#39;s center of mass.
At low temperatures (below T=400K) the dominating mechanism responsible for the
displacement of the cluster&#39;s center of mass is the periphery (or edge) diffusion of the
atoms. At high temperatures (above T=800K) the dissociation and recombination of
the clusters becomes more and more important.</p>