Photoemission core level shifts in Gd silicides

Abstract

Photoemission core spectra from Gd silicides (Gd 3Si 5, GdSi and Gd 5Si 3) are presented. With respect to pure crystalline Si the Si 2 p and 2 s levels shift toward lower binding energies as follows: 0.4 eV in Gd 3Si 5, 0.7 eV in GdSi and 1.2 eV in Gd 5Si 3. On the contrary, the Gd levels (4 f, 5 p, 4 d and 4 p) do not shift within the experimental sensitivity. The observed shifts are discussed in connection with the available information on the valence electron states of Gd silicides.