Auxiliary-field quantum Monte Carlo calculations of the structural properties of nickel oxide

TL;DR

This paper applies auxiliary-field quantum Monte Carlo to study the structural properties of nickel oxide, addressing finite size and basis set errors, and benchmarking against experimental and theoretical data.

Contribution

It demonstrates the effectiveness of AFQMC in accurately modeling strongly correlated materials like NiO using periodic Gaussian basis sets.

Findings

AFQMC provides results in good agreement with experimental data.

Finite size effects significantly influence the accuracy of calculations.

Benchmarking shows AFQMC outperforms some existing theoretical methods.

Abstract

Auxiliary-field quantum Monte Carlo (AFQMC) has repeatedly demonstrated itself as one of the most accurate quantum many-body methods, capable of simulating both real and model systems. In this article we investigate the application of AFQMC to realistic strongly correlated materials in periodic Gaussian basis sets. Using nickel oxide (NiO) as an example, we investigate the importance of finite size effects and basis set errors on the structural properties of the correlated solid. We provide benchmark calculations for NiO and compare our results to both experiment measurements and existing theoretical methods. (LLNL-JRNL-752156)