Magnetism in Exact Exchange Density Functional Theory

TL;DR

This paper investigates the magnetic properties of FeAl using exact exchange density functional theory, demonstrating improved agreement with experimental data through detailed exchange field modeling.

Contribution

It introduces an implementation of exact exchange DFT within an all-electron full potential method to accurately predict magnetic properties of intermetallic compounds.

Findings

FeAl is magnetic with a moment of 0.70 μB

Better agreement with experimental binding energy than previous methods

Orbital dependent exchange potential captures exchange field asymmetry

Abstract

The magnetic properties of the intermetallic compound FeAl are investigated using exact exchange density functional theory. This is implemented within a state of the art all-electron full potential method. We find that FeAl is magnetic with a moment of 0.70 $\mu_B$, close to the LSDA result of 0.69 $\mu_B$. A comparison with the non-magnetic density of states with experimental negative binding energy result shows a much better agreement than any previous calculations. We attribute this to the fine details of the exchange field, in particular its asymmetry, which is captured very well with the orbital dependent exchange potential.