Electronic band structure and the X-ray photoemission spectrum of UCu5In

Abstract

Abstract The family of compounds UCu5M (M ≡ Al, In or Sn) is characterized by the coexistence of magnetic order (antiferromagnetic for M ≡ Al and In; ferri-magnetic for M ≡ Sn) and Kondo lattice effects, by moderate electronic specific heat enhancement (γ/γ0 ≈ 8 for Al; γ/γ0 ≈ 11 for both In and Sn) and possibly a mixed-valence ground state. The electronic band structure was calculated by the tight-binding linear muffin-tin orbital method in the atomic sphere approximation. The electronic structure of UCu5In not unexpectedly shows marked similarities to the electronic structure of the other compounds of the family. The valence band, having a width of about 6eV, is due to prevalent contributions from the Cu 3d and U 5f electrons; the peak from the 5f electrons is situated just above the Fermi level. The X-ray photoemission spectra were taken in vacuum of 5 × 10−10 Torr from the sample surface prepared in situ. Satisfactory agreement between the measured spectrum and that obtained from the calculated electronic structure has been achieved.