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In this work we describe two different models for interpreting and predicting Reflection Electron Energy Loss (REEL) spectra and we present results of a study on metallic systems comparing the computational cost and the accuracy of these techniques. These approaches are the Monte Carlo (MC) method and the Numerical Solution (NS) of the Ambartsumian-Chandrasekhr equations. The former is based on a statistical algorithm to sample the electron trajectories within the target material for describing the electron transport. The latter relies on the numerical solution of the Ambartsumian-Chandrasekhar equations using the invariant embedding method. Both methods receive the same input parameters to deal with the elastic and inelastic electron scattering. To test their respective capability to describe REEL experimental spectra, we use copper, silver, and gold as case studies. Our simulations include both bulk and surface plasmon contributions to the energy loss spectrum by using the effective electron energy loss functions and the relevant extensions to finite momenta. The agreement between MC and NS theoretical spectra with experimental data is remarkably good. Nevertheless, while we find that these approaches are comparable in accuracy, the computational cost of NS is several orders of magnitude lower than the widely used MC. Inputs, routines and data are enclosed with this manuscript via the Mendeley database.

The dynamics of graphene oxide (GO) reduction process is investigated by the electron spectroscopy. GO samples were obtained by the standard Hummers method with the subsequent thermal treatment at different temperatures. Photoelectron emission spectra (PES) of C 1s core level and its energy loss range are analyzed using the invariant imbedding principle. The differential single scattering inelastic cross sections xin(Δ) of all the GO samples were derived by using the fitting procedure. Simulation of PES is performed by making use of the partial intensity approach. The cross sections dynamics analysis shows the reduction process of the graphene structure with increasing annealing temperature. Thermal treatment at a temperature of 600 °C results in the appearance of π-plasmon peak.