Estimation of the structure of binary Ag–Cu nanoparticles during their crystallization by computer simulation

Binary nanoparticles of an alloy of copper and silver are of great practical interest due to the possibility of fine tuning the plasmonic effects present in them by changing the composition, size, shape, and structure of the nanoparticles. In the present work, the processes of formation of the internal structure of Ag–Cu nanoparticles depending on their target chemical composition, size and intensity of thermal exposure were studied by computer simulation. For this, the computer simulation of the process of crystallization of Ag–Cu nanoparticles with a diameter of 2.0–8.0 nm with an atomic copper content ranging from 10 to 50% was performed using the molecular dynamics method based on the tight-binding potential. To imitate the removal of thermal energy from nanoparticles, an Andersen thermostat was used with three different rates corresponding to cooling times of 0.5, 1.5, and 2.5 ns. Based on the results of the analysis of the available experimental data and the results of the computer simulation, it was concluded that it is possible to control the internal structure and shape of Ag–Cu nanoparticles in order to shift the plasmon resonance peak and enhance it.