Unquenched large orbital magnetic moment in NiO

Abstract

The magnetic properties of NiO are investigated by incorporating the spin-orbit interaction in the LSDA + U scheme. It is found that a large part of the orbital moment remains unquenched in NiO. The orbital moment contributes about ${\ensuremath{\mu}}_{L}=0.29{\ensuremath{\mu}}_{B}$ to the total magnetic moment of $M=1.93{\ensuremath{\mu}}_{B},$ which leads to an orbital-to-spin angular momentum ratio of $L/S=0.36.$ The theoretical values are in good agreement with recent magnetic x-ray scattering measurements.