Structural transition and melting of onion-ring Pd-Pt bimetallic clusters

We use canonical Monte Carlo simulations to study the melting of icosahedral and decahedral onion-ring Pd-Pt bimetallic clusters consisting of 147 atoms. Structural transition from decahedron to icosahedron-like is found for the decahedral onion-ring 147-atom Pd-Pt cluster before melting. Also, the melting point of the decahedral onion-ring 147-atom Pd-Pt cluster is lower than the corresponding icosahedral cluster. In addition, at the higher temperatures after melting, the four-shell onion-ring structure becomes unstable, and can be transformed into the three-shell onion-like structure. (C) 2008 Elsevier B.V. All rights reserved.