Characteristic Electron Energy Losses in Sodium and Potassium

The characteristic electron energy-loss spectra of sodium and potassium have been obtained with improved resolution. Each spectrum was found to exhibit normal surface and volume plasma-oscillation loss peaks; the anomalies reported previously were not observed. Intrinsic surface and volume energy losses of 3.82±{}0.10 eV and 5.85±{}0.05 eV in sodium, and 2.75±{}0.10 eV and 4.05±{}0.15 eV in potassium, are reported.