The electronic structure, crystal fields, and magnetic anisotropy in RECo$_5$ magnets

Abstract

The current progress in describing rare-earth-based magnets' electronic structure and magnetic properties is discussed. We use several currently popular electronic structure methods to show the typical values of critical parameters that define the physics of RECo$_5$ (RE = rare earth atom) materials. The magnetic moments and anisotropy of 4\textit{f} atoms are obtained using several approaches, including anisotropic 4\textit{f}-charge density-constrained DFT and DFT+HI methods. We also suggest the introduction of 'penalty' functional for obtaining correct variational total energy in the traditional Hund's rule-constrained DFT-based techniques. The applicability and future extensions are discussed. The proposed combination of methods is potentially suitable for high-throughput computational searches of new rare-earth-containing magnetic materials.