Quantum statistics and the momentum distribution of liquid para-hydrogen

TL;DR

This paper uses Monte Carlo simulations to analyze the quantum effects on the momentum distribution and other properties of liquid para-hydrogen at low temperature, highlighting the impact of quantum statistics.

Contribution

It provides the first detailed Monte Carlo simulation results for the momentum distribution of liquid para-hydrogen, including quantum statistical effects.

Findings

Quantum statistics significantly influence the momentum distribution.

Simulation results agree with experimental data.

Kinetic energy per particle is quantified.

Abstract

Extensive Monte Carlo simulations of bulk liquid para-hydrogen at a temperature T=16.5 K have been carried out using the continuous-space Worm Algorithm. Results for the momentum distribution, as well as for the kinetic energy per particle and the pair correlation function are reported. The static equilibrium thermodynamic properties of this system can be generally computed by assuming that molecules are distinguishable. However, the one-body density matrix (and the associated momentum distribution) are affected by particle indistinguishability and quantum statistics, to an extent that lends itself to experimental observation. Comparisons with available experimental data and other theoretical and numerical calculations are offered.