A molecular dynamics study on cooling rate effect on atomic structure of solidified silver nanoparticles
The atomic structures and solidification point of silver nanoparticles (SNPs) are studied in aseries of molecular dynamics simulations based on the empirical embedded atom methods (EAM). Thesolidification point is calculated from the extracted potential energy during the cooling process, whereasthe atomic structures are analyzed using the common neighbor (CN) method. The results indicate that thestructures of the solidified SNPs are very sensitive to both the applied cooling rate and the particle size. Wefind the critical cooling rate where a glassy structure is observed. Below the critical rate, polycrystallinenanoparticles are formed, where the percentage of the close-packed structures, i.e., FCC and HCP, decreaseswith increasing cooling rate. Moreover, the proportion of those structures is always larger with a biggerparticle size for an identical applied cooling rate. The findings in this study provide useful information formany practical applications where the nanostructure strongly affects thermal management and operationalefficiency.