Monte Carlo Analysis of a New Interatomic Potential for He

TL;DR

This paper compares a revised interatomic potential for helium using Monte Carlo methods, showing improvements in some properties but still underestimating energy, with potential for further refinement by including three-body interactions.

Contribution

It introduces a revised interatomic potential for helium and evaluates its performance against the Aziz potential using Monte Carlo simulations.

Findings

Revised potential better describes the equation of state for liquid helium.

Energy per particle from the new potential is lower than experimental values.

Including three-body interactions could improve energy estimates.

Abstract

By means of a Quadratic Diffusion Monte Carlo method we have performed a comparative analysis between the Aziz potential and a revised version of it. The results demonstrate that the new potential produces a better description of the equation of state for liquid $^4$He. In spite of the improvement in the description of derivative magnitudes of the energy, as the pressure or the compressibility, the energy per particle which comes from this new potential is lower than the experimental one. The inclusion of three-body interactions, which give a repulsive contribution to the potential energy, makes it feasible that the calculated energy comes close to the experimental result.