Quantum Monte Carlo determination of the principal Hugoniot of deuterium

TL;DR

This paper uses advanced Quantum Monte Carlo methods to accurately determine the principal Hugoniot of deuterium, considering quantum effects and electronic excitations, and compares results with experimental data.

Contribution

It provides a comprehensive Quantum Monte Carlo analysis of deuterium's Hugoniot, including low and high P,T conditions, improving accuracy over previous studies.

Findings

Close agreement with experimental data at low P,T

Predicted higher compressibility at high P,T than experiments

Enhanced understanding of nuclear quantum effects and electronic excitations

Abstract

We present Coupled Electron-Ion Monte Carlo results for the principal Hugoniot of deuterium together with an accurate study of the initial reference state of shock wave experiments. We discuss the influence of nuclear quantum effects, thermal electronic excitations, and the convergence of the energy potential surface by wave function optimization within Variational Monte Carlo and Projection Quantum Monte Carlo methods. Compared to a previous study, the new calculations also include low pressure-temperature (P,T) conditions resulting in close agreement with experimental data, while our revised results at higher (P,T) conditions still predict a more compressible Hugoniot than experimentally observed.