The electronic structures of U3P4 and U3As4 single crystals are probed by x-ray and vacuum ultraviolet photoemission spectroscopy (XPS and UPS) as well as by x-ray bremsstrahlung isochromat spectroscopy (BIS). The BIS spectra show a broad peak at 1.8 eV above the Fermi level (EF) with a noticeable tail. Its energy separation of 2.5 eV from the U 5f UPS peak is larger than U5f,5f=1.2 eV. This difference is interpreted as mostly due to the spin-orbit splitting of the U 5f state. The U 4f core XPS has shown rather an asymmetric shape with a tail toward larger binding energies (EB). A satellite not directly observable in the experimental spectrum is revealed at 5.4 eV by deconvolution. Based on an extended Anderson impurity model, it is interpreted as the p-d antibonding state. The appreciable density of the U 6d state near EF strongly influences the photoemission spectra.
ASJC Scopus subject areas
- Condensed Matter Physics