Pressure-induced transitions in FePS$_3$: Structural, magnetic and electronic properties

TL;DR

This study uses first-principles calculations to explore pressure-induced structural, magnetic, and electronic transitions in FePS$_3$, revealing a novel high-pressure phase and insights into the emergence of metallicity and magnetic states.

Contribution

It provides a theoretical interpretation of experimental observations and predicts a new high-pressure phase with unique properties in FePS$_3$.

Findings

Identification of pressure-induced phase transitions.

Prediction of a novel high-pressure phase.

Insights into the origin of metallicity under pressure.

Abstract

FePS$_3$ is a prototype van der Waals layered antiferromagnet and a Mott insulator under ambient conditions, which has been recently reported to go through a pressure-induced dimensionality crossover and an insulator-to-metal transition. These transitions also lead to the appearance of a novel magnetic metallic state. To further understand these emergent structural and physical properties, we have performed a first-principles study using van der Waals and Hubbard $U$ corrected density functional theory including a random structure search. Our computational study attempts to interpret the experimental coexistence of the low- and intermediate-pressure phases and we predict a novel high-pressure phase with distinctive dimensionality and different possible origins of metallicity.