Valence sensitivity of Fe-L2,3 white-line ratios extracted from EELS

Several authors have shown that the EELS white-line intensity ratio (WLR) of 3d transition metals can be used to measure the metal valency [1,2]. For the WLR extraction from EEL edge spectra various procedures have been proposed [2,3], including fitting and 2nd derivative methods. The aim of the present study is to evaluate quantitatively the influence of the extraction method on the differentiability of noisy Fe-L2,3 white-line spectra belonging to two different valencies.