Coalescing Dynamics between Ag55 and Cu55 Clusters as Well as Thermodynamics during Cooling the Coalesced Clusters from Atomic Simulations

J Phys Chem A. 2023 Aug 24;127(33):6881-6891. doi: 10.1021/acs.jpca.3c02419. Epub 2023 Aug 9.

Abstract

Molecular dynamics simulations are performed to investigate the coalescing processes between a Cu55 cluster with a liquid, FCC, or Ih structure and a Ag55 cluster in liquid, as well as the structural changes of the coalesced clusters during the cooling process. The simulation results show that the initial structure of the Ag and Cu clusters significantly affects the coalescence stages and the structures after coalescence. There are apparent rotations of the Ag cluster with the liquid structure relative to the Cu cluster with the liquid structure when they are approaching. Before the formation of a neck, the Cu cluster with the Ih structure is more stable and less likely to lose its structure compared to the Cu cluster with the FCC structure. During the cooling process, the coalesced clusters will form different packing structures, including Ih and metastable core/shell structures. The Lode-Nadai values reveal the loading states on the atoms when the two clusters collide. The thermodynamic behaviors during the cooling process were investigated to better understand the order degree of the packing structures and the structural transition processes.