Towards an effective potential for the monomer, dimer, hexamer, solid and liquid forms of hydrogen fluoride

TL;DR

This paper introduces a new simple two-body potential for hydrogen fluoride that accurately models its various phases, enabling efficient simulations while capturing key physical properties.

Contribution

A novel, computationally efficient two-body potential for HF that fits data across gas, liquid, and solid phases, suitable for molecular simulations.

Findings

Successfully reproduces observables of HF in multiple phases

Models intra- and inter-molecular interactions effectively

Identifies limitations and suggests future improvements

Abstract

We present an attempt to build up a new two-body effective potential for hydrogen fluoride, fitted to theoretical and experimental data relevant not only to the gas and liquid phases, but also to the crystal. The model is simple enough to be used in Molecular Dynamics and Monte Carlo simulations. The potential consists of: a) an intra-molecular contribution, allowing for variations of the molecular length, plus b) an inter-molecular part, with three charged sites on each monomer and a Buckingham "exp-6" interaction between fluorines. The model is able to reproduce a significant number of observables on the monomer, dimer, hexamer, solid and liquid forms of HF. The shortcomings of the model are pointed out and possible improvements are finally discussed.