Eur. Phys. J. B (2017) 90: 113
https://doi.org/10.1140/epjb/e2017-80028-5

Regular Article

Diffusion of Al dimers on the surface of Mg clusters

¹ College of Science, Hunan Institute of Engineering, Xiangtan 411104, P.R. China
² College of Materials Science and Engineering, Hunan University, Changsha 410082, P.R. China

^a e-mail: daixiongying@126.com

Received: 12 January 2017
Received in final form: 21 March 2017
Published online: 19 June 2017

Abstract

The surface diffusion of Al dimmers on Mg clusters with hexahedral structure was studied using the combination of quenched molecular dynamics and the embedded atom method. The system energy barriers of typical minimum energy diffusion paths for Al dimers on the Mg clusters were calculated using the Nudged Elastic Band method. In our study range (153–4061 atoms), the binding energies on the (0001) facets and the (101) facets differed, the binding energy on the former was lower than that on the latter. Moreover, cluster size only slightly influenced the binding energy values. Two possible diffusion paths were studied. Results showed that the diffusion of the dimer on the (0001) facet easily occurred at low temperatures. Furthermore, the interaction between the two atoms of the dimer facilitated the dimer crossing of the step edge between the (101) facets by hopping mechanism.