Benchmarking First-Principles Approaches for Extracting Magnetic Exchange Interactions

TL;DR

This paper systematically compares three first-principles methods for extracting magnetic exchange interactions, highlighting their accuracy, efficiency, and practical workflow considerations across multiple antiferromagnetic compounds.

Contribution

It introduces a framework for minimal supercell selection in the FSTE method and provides a comprehensive comparison of LSTE, FSTE, and LKAG approaches.

Findings

LSTE and FSTE produce nearly identical exchange parameters.

LKAG captures dominant interactions but shows quantitative deviations.

LSTE offers the best balance of computational efficiency and accuracy.

Abstract

Magnetic exchange interactions govern the macroscopic magnetic behavior of solids and underpin both fundamental spin phenomena and emerging technologies. The accurate and efficient determination of these interactions is therefore critical for predictive modeling of magnetic materials. Here we present a systematic first-principles comparison of three widely used approaches-the Least-Squares Total Energy (LSTE), the Four-State Total Energy (FSTE), and the Green's function-based Liechtenstein \textit{et al.} (LKAG) methods-applied to thirteen antiferromagnetic compounds. We introduce an framework for identifying the minimal supercells required for an accurate exchange parameter extraction in the FSTE method, significantly reducing computational cost while preserving precision. Our results show that LSTE and FSTE yield nearly identical exchange parameters, whereas the LKAG method reproduces the dominant exchange interactions but exhibits quantitative deviations. A detailed analysis of computational efficiency versus accuracy reveals that the LSTE scheme offers the most favorable balance, establishing a general, reproducible, and scalable workflow for Heisenberg mapping, while the FSTE approach remains the most straightforward for extracting specific exchange interactions.