Phenomenology of the heating, melting and diffusion processes in Au nanoparticles

Abstract

The paper reports the results of a MD study of the heating and melting process of Au nanoparticles. A physico-chemical isomerization-like model of the melting step accounts for structural, thermodynamic and diffusion results, trends and interrelations.

Systematics of vibrational properties of Au nanoparticles: a molecular dynamics approach

“…On that basis a consistent picture of the energetic and structural effects of the heating and melting process was reported. 12,13…”

“…Previous studies by the present authors dealt with the effect of size and temperature upon the structural, thermodynamic and diffusion properties, as well as the melting behavior of spherical Au nanoparticles. 12,13 To that aim, extensive use was made of MD simulations, to determine the caloric curves as well as a variety of physical parameters, i.a. the Lindemann index, the root mean square displacement, the Lindemann ratio, and the radial distribution function.…”

“…On that basis a consistent picture of the energetic and structural effects of the heating and melting process was reported. 12,13 Building on the previous studies, the present work concentrated on the size dependence of the vibrational properties of a similar set of Au nanoparticles. As in our previous works, MD simulations as implemented in the LAMMPS code were adopted, and two interatomic potentials (EAM and MEAM) were tested.…”

“…The present work is part of a long-term research project aimed at establishing the temperature and size dependence of the structural, thermodynamic and kinetic properties, as well as the melting transition in Au nanoparticles, by using MD simulations. 12,13 The thermodynamic part of the previous work concentrated on the energetics, by relying upon an accurate MD account of the ''caloric curves'' and the cohesive energy of the nanoparticles. The purpose of the present work is to go one step further by focusing on the properties which are related to the entropy part of the Gibbs energy.…”

Invariant surface elastic properties in FCC metals and their correlation to bulk properties revealed by machine learning methods

“…These potentials are fit to give the bulk elastic constants, cohesive energy, low-index surface energies, and stacking fault energy. These potentials have been successfully used in other studies to simulate the mechanical behavior of nanostructures [30][31][32][33][34].…”