Direct spectroscopic evidence was reported for atom migration during the initial stage of electron irradiation in spinel MgAl2O4. Time-dependent electron energy-loss spectroscopy of the Mg and Al L23 edges showed that both Mg and Al had a tendency to occupy the octahedral interstices under electron irradiation, along with a slight expansion of the Al–O bonding distance, but there was little change in the structural framework of oxygen. The process was irreversible at room temperature.

Electronic Ionization Induced Atom Migration in Spinel MgAl2O4. N.Jiang, J.C.H.Spence: Journal of Nuclear Materials, 2010, 403[1-3], 147-51