Dependence of self-diffusion coefficient, surface energy, on size, temperature, and Debye temperature on size for aluminum nanoclusters

TitleDependence of self-diffusion coefficient, surface energy, on size, temperature, and Debye temperature on size for aluminum nanoclusters
Publication TypeJournal Article
Year of Publication2012
AuthorsTaherkhani, F, Akbarzadeh, H, Abroshan, H, Fortunelli, A
JournalFluid Phase Equilibria
Volume335
Pagination26–31
ISSN03783812 (ISSN)
KeywordsAluminum, Atoms, Average coordination number, Bulk-limit, Cluster sizes, Cohesive energies, Debye temperature, Diffusion in liquids, Interfacial energy, molecular dynamics, molecular dynamics simulation, Molecular dynamics simulations, Nano-scale system, Nanoclusters, Self-diffusion coefficient, Self-diffusion coefficients, Size effect, Size effects, Surface energy, Temperature increase
Abstract

Molecular dynamics simulations are performed to investigate the surface energy and self-diffusion coefficient in aluminum nanoclusters (Al N) as a function of temperature, T (T=300-1100K), and size (N=108-4000 atoms, with N the number of atoms in the cluster), with the self-diffusion coefficient compared with the bulk limit. Debye temperature, cohesive energy, and average coordination number of Al N are also explored as a function of the cluster size. The surface energy decreases as a function of size as well as temperature, and becomes very small at sizes larger than N≥2000, while the average coordination number and the Debye temperature increase as a function of nanocluster size. The self-diffusion coefficient decreases with increasing size as N -2/3, while increasing as a function of temperature, and exhibits values substantially larger than in the bulk, quantitatively confirming the much greater structural freedom encountered of nanoscale systems. © 2012 Elsevier B.V.

DOI10.1016/j.fluid.2012.08.011