  High-energy, local multiplet excitations of the d-electrons are revealed in
our inelastic neutron scattering measurements on the prototype magnetic
insulator NiO. These become allowed by the presence of both non-zero crystal
field and spin-orbit coupling. The observed excitations are consistent with
optical, x-ray, and EELS measurements of d-d excitations. This experiment
serves as a proof of principle that high-energy neutron spectroscopy is a
reliable and useful technique for probing electronic excitations in systems
with significant crystal field and spin-orbit interactions.
