Adapting FEFF to 5f angular momentum coupling

It is demonstrated here that the spectral simulation program FEFF can be adapted to include the effects of 5f total angular momentum coupling in the fluorite actinide dioxide systems ThO2, UO2, and PuO2. N-4,N-5 x-ray absorption spectra produced with this modified FEFF approach will be compared to the previous experimental results, obtaining a strong agreement between the two.