Exchange interactions and magnetic phases of transition metal oxides: benchmarking advanced ab initio methods

TL;DR

This study evaluates the magnetic properties of MnO and NiO under pressure using advanced ab initio methods, demonstrating improved accuracy and internal consistency over traditional approaches.

Contribution

It benchmarks hybrid density functional theory and variational pseudo-self-interaction correction methods for transition metal oxides, showing their effectiveness in predicting magnetic phases.

Findings

Advanced functionals improve magnetic property predictions.

Methods show internal consistency despite methodological differences.

Results align well with experimental data.

Abstract

The magnetic properties of the transition metal monoxides MnO and NiO are investigated at equilibrium and under pressure via several advanced first-principles methods coupled with Heisenberg Hamiltonian MonteCarlo. The comparative first-principles analysis involves two promising beyond-local density functionals approaches, namely the hybrid density functional theory and the recently developed variational pseudo-self-interaction correction method, implemented with both plane-wave and atomic-orbital basis sets. The advanced functionals deliver a very satisfying rendition, curing the main drawbacks of the local functionals and improving over many other previous theoretical predictions. Furthermore, and most importantly, they convincingly demonstrate a degree of internal consistency, despite differences emerging due to methodological details (e.g. plane waves vs. atomic orbitals)