The spin angular gradient approximation in the density functional theory

TL;DR

This paper introduces a spin angular gradient approximation for the exchange correlation magnetic field in density functional theory, enabling a more consistent spin dynamical approach without additional potential approximations.

Contribution

It proposes a novel correction method that enhances the density functional formalism for spin dynamics, compatible with full potential band structure calculations.

Findings

Direct potential exchange in 3d magnets is small

Kinetic exchange dominates in 3d metals

Method improves spin dynamic modeling

Abstract

A spin angular gradient approximation for the exchange correlation magnetic field in the density functional formalism is proposed. The usage of such corrections leads to a consistent spin dynamical approach beyond the local approximation. The proposed technique does not contain any approximations for the form of potential and can be used in modern full potential band structure methods. The obtained results indicate that the direct 'potential' exchange in 3d magnets is rather small compared to the indirect 'kinetic' exchange, thus justifies the dynamical aspect of the local density approximation in 3d metals.