Observation of 5f intermediate coupling in uranium x-ray emission spectroscopy

The first observation of Intermediate Coupling effects in the occupied 5f states has been made using x-ray Emission Spectroscopy (XES). In the past, the impact of Intermediate Coupling of the 5f states in actinides has long been observed and quantified, using x-ray Absorption Spectroscopy (XAS) to probe the unoccupied 5f states, providing great insight into the enigma of 5f electronic structure. However, no measure of its effects in the occupied states had been reported before this. Moreover, because the 5f occupied states in UF4 are almost completely of 5f5/2 character, the observed effect in XES is twice that in XAS for UF4.