The analysis procedure of valence-electron excitation spectra is described with an example of diamond. It includes a subtraction of zero-loss intensity, a deconvolution of multiple inelastic scattering intensities, a derivation of a loss-function, Kramers-Kronig analysis and a calculation of optical constants. A split of inner-shell electron levels due to the spin-orbit interaction and the crystal-field splitting of 3d electron orbital energies are explained with an example of VO2 spectra. A development of an X-ray emission spectroscopy instrument for a transmission electron microscopy to obtain a density of states of valence bands is briefly described.
