Argon force field revisited: a molecular dynamic study

TL;DR

This study improves argon force fields by adjusting Lennard-Jones parameters to accurately reproduce both the liquid-vapor phase diagram and surface tension using molecular dynamics simulations.

Contribution

It introduces a systematic scaling approach to optimize argon force fields for multiple properties simultaneously.

Findings

All force fields converge in a specific region of parameter space.

Optimal parameters differ from original force field values.

The study provides parameter intervals for accurate property reproduction.

Abstract

We report the improvement of five argon force fields by scaling Lennard-Jones energy ($\epsilon$) and distance ($\sigma$) parameters to reproduce liquid-vapor phase diagram and surface tension simultaneously, with molecular dynamics. Original force fields reproduce only liquid-vapor phase diagram among other properties except surface tension. Results showed that all force fields converge in a nearby region in the $\epsilon$-$\sigma$ phase space, which is different from the original values. This study gives the intervals where the numerical values of $\epsilon$ and $\sigma$ reproduce both properties mentioned above.