Evaluation of Force Fields for Molecular Dynamics Simulations of Platinum in Bulk and Nanoparticle Forms

TL;DR

This study evaluates nine empirical force fields to determine the most accurate for simulating platinum's bulk and nanoparticle properties, aiding the design of nanoparticle-based applications.

Contribution

It identifies the best force field among nine for modeling platinum in bulk and nanoparticle forms based on comprehensive property evaluations.

Findings

The embedded atom method with a specific parameter set best predicts platinum properties.

None of the force fields perfectly match all experimental and quantum data.

The study guides future molecular dynamics simulations of platinum nanoparticles.

Abstract

Understanding the size- and shape-dependent properties of platinum nanoparticles is critical for enabling the design of nanoparticle-based applications with optimal and potentially tunable functionality. Toward this goal, we evaluated nine different empirical potentials with the purpose of accurately modeling faceted platinum nanoparticles using molecular dynamics simulation. First, the potentials were evaluated by computing bulk and surface properties-surface energy, lattice constant, stiffness constants, and the equation of state-and comparing these to prior experimental measurements and quantum mechanics calculations. Then, the potentials were assessed in terms of the stability of cubic and icosahedral nanoparticles with faces in the {100} and {111} planes, respectively. Although none of the force fields predicts all the evaluated properties with perfect accuracy, one potential -- the embedded atom method formalism with a specific parameter set -- was identified as best able to model platinum in both bulk and nanoparticle forms.