X-ray transitions for studying the electronic structure of5dmetals

X-ray fluorescence transitions of the type $5\overrightarrow{d}4p$ have been measured for the $5d$ compounds Ta, TaC, and ${\mathrm{Ta}}_2{\mathrm{O}}_5.$ The measured Ta $N_3$ x-ray emission spectra are compared with band-structure calculations and it is concluded that the soft-x-ray transitions can be used to study occupied $5d$ electronic states in materials with $5d$ elements.