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.
@article{arxiv.1106.4634,
title = {Probing high-energy electronic excitations using inelastic neutron scattering},
author = {Young-June Kim and A. P. Sorini and C. Stock and T. G. Perring and J. van den Brink and T. P. Devereaux},
journal= {arXiv preprint arXiv:1106.4634},
year = {2012}
}