The onset of a liquid-vapour transition in metallic nanoparticles

TL;DR

This paper investigates the liquid-vapor transition in metallic nanoparticles, specifically lead nanodroplets, using molecular dynamics simulations to analyze their structural and energetic behaviors near melting points.

Contribution

It provides new insights into the shape, stability, and disassembly mechanisms of lead nanodroplets at various sizes and temperatures, including shape oscillations modeled by the nuclear liquid drop model.

Findings

Small clusters tend to form non-spherical shapes and sometimes split into two droplets.

Larger clusters disassemble primarily through evaporation of monomers.

Shape oscillations are characterized using the nuclear liquid drop model.

Abstract

We study lead nanodroplets containing 147 to 1415 atoms at temperatures ranging from the bulk melting point up to the beginning of the evaporation regime. Molecular dynamics simulation and an embedded atom potential are used. The structures, total energies, and mobility of atoms in the clusters are analyzed. We found that the liquid cluster of 147 atoms shows a pronounced tendency to form non-spherical shapes, and sometimes separates into two droplets. Bigger clusters disassemble by evaporation of monomers. We also explore shape oscillations of these nanodroplets using the nuclear liquid drop model.