Electronic Excitations in Some Transition Metals and Their Oxides. Characteristic Energy Loss Measurements up to 50 eV

The characteristic energy losses suffered by a 20 keV electron beam through thin films of some transition metals (Sc, Y, Zr, Hf) and of their oxides are measured using a magnetic spectrograph up to 50 eV. The energy loss function — Im 1/ε and the complex dielectric constant are calculated. It is shown that the electron excitation spectra of metals contain two main contributions in this energy range: one due to collective excitations of the conduction electrons, the other to the excitation of inner p‐electrons. In the case of oxides the spectra display three strong structures: there are probably two collective excitations of valence electrons followed by the excitation of inner p‐electrons of the metal.