Observation of orbital moment in NiO

The spin- and orbital-moment magnetization form factors in NiO have been measured using magnetic x-ray scattering. The polarization analysis of nonresonant magnetic-scattering intensities has evidenced a large contribution from the orbital moment to the total magnetization. In the antiferromagnetic phase, the orbital moment contributes $17\ifmmode\pm\else\textpm\fi{}3%$ to the magnetization density.