Local spin-density functional theory of noncollinear magnetism (invited)

Abstract
We apply spin‐density functional theory (SDF) to describe noncollinear magnetism; i.e., self‐consistent energy‐band calculations based on the local approximation to SDF theory are presented in which the magnetization associated with different atoms in a unit cell is allowed to point along different, noncollinear directions. In contrast to older work (e.g., by You and Heine and by Oguchi, Terakura, and Hamada) the present calculations are (1) self‐consistent, (2) provide the total energy, and (3) provide the spin‐quantization axes. In our applications we deal with noncollinear antiferromagnets γ‐FeMn and perovskites Mn3GaN and show that their total energies are minimized in tetrahedral and triangular magnetic structures, respectively, first proposed by Kouvel and Kasper.