Electron-energy loss spectra for the first transition series

Abstract The energy loss of electrons (incident energy 60 kev) in thin evaporated films of the metals V, Cr, Fe, Co, Ni and Cu of the first transition series has been determined in transmission for the spectral region 3-80 ev. The complexity of the spectrum increases along the series as the 3d shell is completed. In V and Cr the main peak (22-25 ev) in the spectrum is attributed to a collective excitation (4s + 3d electrons); the positions of similar peaks in the spectra of Fe, Co, Ni and Cu (18-21 ev) are affected by one-electron excitations above or below the plasmon eigenvalue. The loss at about 10 ev observed in all spectra is attributed to the collective excitation of bonding electrons. The structure at higher energy loss values (36-65 ev) corresponds to the M2,3 x-ray absorption edge; the intense and broad peak 5 ev above this edge in V decreases in intensity along the series and is not evident in the spectrum of Co.