Changes in the structure of nanoclusters of nickel and copper under the action of temperature

Molecular dynamics with tight-binding potential was used to study the processes of thermal impact on Ni nanoclusters with radii of up to 0.8 nm. The performed simulation demonstrated that under the action of heating, there is a structural transition from the initial face-centered cubic phase to a icosahedral modification. It was observed that upon an increase of cluster size, the transition temperature shifted to the melting point of the cluster. The obtained relationships were tested on the copper nanoparticles of similar size. It was concluded that the size of a metal cluster of 200–250 atoms is probably the limit below which it is impossible to maintain the initial face-centered cubic modification under actual conditions of exploitation.