Progress and Challenges in Ab Initio Simulations of Quantum Nuclei in Weakly Bonded Systems

TL;DR

This paper reviews recent advances in ab initio simulations of quantum nuclei in weakly bonded systems, highlighting methodological progress, remaining challenges, and the impact of nuclear quantum effects on material properties.

Contribution

It provides a comprehensive overview of simulation methods for large systems that include quantum effects of electrons and nuclei, and discusses future challenges in the field.

Findings

Simulation methods now enable large-scale quantum nuclear modeling.

Nuclear quantum effects significantly influence electronic properties.

Challenges remain in accurately including nuclear quantum effects beyond harmonic approximations.

Abstract

Atomistic simulations based on the first-principles of quantum mechanics are reaching unprecedented length scales. This progress is due to the growth in computational power allied with the development of new methodologies that allow the treatment of electrons and nuclei as quantum particles. In the realm of materials science, where the quest for desirable emergent properties relies increasingly on soft weakly-bonded materials, such methods have become indispensable. In this perspective, an overview of simulation methods that are applicable for large system sizes and that can capture the quantum nature of electrons and nuclei in the adiabatic approximation is given. In addition, the remaining challenges are discussed, especially regarding the inclusion of nuclear quantum effects (NQE) beyond a harmonic or perturbative treatment, the impact of NQE on electronic properties of weakly-bonded systems, and how different first-principles potential energy surfaces can change the impact of NQE on the atomic structure and dynamics of weakly bonded systems.