Photoemission studies and electronic structure of U(2)T(2)In (T = Ni, Rh, Pt) compounds

The electronic structure of the tetragonal U(2)T(2)In (T = Ni, Rh, Pt) compounds in the paramagnetic phase were studied by x-ray photoelectron spectroscopy (XPS). Both valence band and core level spectra were analysed. The experimental data are compared with the calculations of the density of states using the tight-binding linear muffin-tin orbital method (TB-LMTO) and full-potential local-orbital full-relativistic method (FPLO). The calculated data reveal a dominant U 5f electron character for the states near the Fermi level E(F) with a small contribution from U 5d, Ni 3d, Rh 4d, Pt 5d and In 5p states. The XPS valence bands of these compounds are characterized by a sharp peak of the U 5f states near the Fermi level (E(F)) and broad peaks of the Ni 3d, Rh 4d and Pt 5d states at about 2.6, 3.2 and 4.0 eV below E(F), respectively. The small change in the position of the U 5f peak with respect to E(F) is -0.35 eV for T = Ni and -0.15 eV for T = Rh and Pt. A satellite between the Ni 2p(1/2) and Ni 2p(3/2) peaks is visible, suggesting that the Ni 3d band is not completely filled, and the existence of a small induced magnetic moment on the Ni atoms cannot be ruled out.