Photoemission studies and electronic structure ofU2T2In (T = Ni,Rh, Pt) compounds

Abstract

The electronic structure of the tetragonalU2T2In (T = Ni,Rh, Pt) compounds in the paramagnetic phase were studied by x-ray photoelectronspectroscopy (XPS). Both valence band and core level spectra were analysed.The experimental data are compared with the calculations of the densityof states using the tight-binding linear muffin-tin orbital method (TB-LMTO)and full-potential local-orbital full-relativistic method (FPLO). The calculateddata reveal a dominant U 5f electron character for the states near the Fermi levelEF with a small contribution from U 5d, Ni 3d, Rh 4d, Pt 5d and In 5p states. The XPS valence bandsof these compounds are characterized by a sharp peak of the U 5f states near the Fermi level(EF) and broad peaks of the Ni 3d, Rh 4d and Pt 5d states at about 2.6, 3.2 and 4.0 eV belowEF, respectively. The small change in the position of the U 5f peak with respect toEF is−0.35 eV forT = Ni and−0.15 eV forT = Rh and Pt. A satellitebetween the Ni 2p1/2 and Ni 2p3/2 peaks is visible, suggesting that the Ni 3d band is not completely filled, and theexistence of a small induced magnetic moment on the Ni atoms cannot be ruledout.