Development of Path Integral Monte Carlo Simulations with Localized Nodal Surfaces for Second-Row Elements

TL;DR

This paper advances fermionic path integral Monte Carlo simulations for heavier elements at lower temperatures by developing localized nodal surfaces, enabling accurate predictions of thermodynamic properties in warm dense matter.

Contribution

It introduces localized nodal surfaces for PIMC, improving simulation accuracy for second-row elements and integrating with DFT-MD results for equation of state calculations.

Findings

Accurate pressure and internal energy predictions for hot, dense silicon.

Consistent equation of state for warm dense matter.

Derived shock Hugoniot curve and characterized fluid structure.

Abstract

We extend the applicability range of fermionic path integral Monte Carlo simulations to heavier elements and lower temperatures by introducing various localized nodal surfaces. Hartree-Fock nodes yield the most accurate prediction for pressure and internal energy that we combine with the results from density functional molecular dynamics simulations to obtain a consistent equation of state for hot, dense silicon under plasma conditions and in the regime of warm dense matter (2.3-18.6 g/cm, 5.0*10^5 - 1.3*10^8 K). The shock Hugoniot curve is derived and the structure of the fluid is characterized with various pair correlation functions.