Phase Transitions and Self-Assembly of Nickel-Palladium Bimetallic Clusters

By implementing replica-exchange Monte Carlo simulations within the multihistogram reweighting techniques, the structural changes in bimetallic thirteen atom Ni-Pd clusters were considered as a function of composition. The interparticle interactions were described using the embedded atom potential and the lowest energy equilibrium structures determined and associated to the mixing degree of the material. In all cases melting and order disorder transitions were encountered by calculating the average constant heat capacity as a function of temperature. The change in Gibbs free energy for the order-disorder transition was determined as a function of composition for each system. The most stable thirteen-atom cluster was used to consider possible self-assembly of multiple clusters in various solvents.