ELECTRON ENERGY LOSSES AND ION POLARIZABILITY IN CERTAIN TRANSITION-METAL OXIDES.

The energy-loss spectra were measured for 20 keV electrons which had passed through films of transition-metal oxides (Sc//2O//3, TiO//2, Cr//2O//3, MnO, Mn//3O//4, Co//3O//4, NiO, Sm//2O//3, EuO, Eu//2O//3, Ho//2O//3, Yb//2O//3, and UO//2). The optical functions were calculated from the spectra. The loss peaks are identified according to the types of excitation. The shift in the observed value of bulk plasmon energy from the theoretical figure for a free electron gas is used to determine the electron molar polarizability of the oxides. The molar values are then used to calculate the electron polarizability of the ions.