First-principles theory of orbital magnetization

Within density-functional theory we compute the orbital magnetization for periodic systems evaluating a recently discovered Berry-phase formula. For the ferromagnetic metals Fe, Co, and Ni we explicitly calculate the contribution of the interstitial regions neglected so far in literature. We also use the orbital magnetization to compute the electron paramagnetic resonance g tensor in paramagnetic systems. Here the method can also be applied in cases where linear-response theory fails, e. g., radicals and defects with an orbital-degenerate ground state or those containing heavy atoms.