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A method for extracting the differential inelastic scattering cross sections of electrons xin(Δ) from the energy spectra of electron spectroscopy is developed. The derived cross sections are verified by interpreting experimental data on electron-energy-loss spectra, X-ray photoelectron spectroscopy, and Auger spectroscopy. The paper highlights existing methods for determining the cross sections xin(Δ) using electron-energy-loss spectra. Inconsistency in analytical solution of the inverse problem (i.e., deconvolution) is shown for calculating the inelastic scattering cross section of electrons xin(Δ). In this paper, the solution of the mathematically ill-posed problem of cross-section retrieval is based on a fitting procedure consisting in multiple direct-problem calculations, i.e., calculations of the electron spectra taking into account both elastic and inelastic multiple scattering events. To implement an efficient fitting algorithm, a high-performance procedure for solving the direct problem of determining the energy spectra of electron spectroscopy is developed. The method for calculating the spectra is based on solution of the boundary problem for the transport equation by using the invariant imbedding method. The procedure developed in this work allows the energy-loss cross sections in the surface layer and in the sample homogeneous bulk layer remote from the surface to be reconstructed. The cross sections xin(Δ) retrieved from experimental data on the electron-energy-loss spectra satisfactorily reproduce the Auger spectroscopy and X-ray photoelectron spectroscopy signals and vice versa: the cross sections xin(Δ) retrieved from the X-ray photoelectron spectroscopy data satisfactorily reproduce the electron-energy loss and Auger spectroscopy spectra. It is shown that for the description of the X-ray photoelectron spectroscopy spectra of Be, Mg, Al, Nb, and W, it is not necessary to use additional mechanisms of energy losses, so-called "intrinsic excitations". [ABSTRACT FROM AUTHOR]

Samples of thermally reduced graphene oxide are studied using differential cross sections for photoelectron inelastic energy losses. We compare different procedures for recovering cross sections from the photoelectron energy spectra resulting from multiple inelastic scattering. It is shown that the cross section for inelastic energy losses (which uniquely characterizes allotropes of carbon) in the sample containing the minimal amount of carbon oxides corresponds the best to pyrolytic graphite. [ABSTRACT FROM AUTHOR]

The dynamics of X-ray photoelectron emission spectra is studied in the region of the 1s carbon line with increasing treatment temperature for graphene-oxide samples. It is established that, as the degree of oxide reduction increases, the role of the mechanism related to energy losses for the excitation of π-plasmon oscillations produced in the presence of sp2 bonds in the carbon sample increases. Spectral analysis shows that the π-plasmon peak is manifested in the spectra of samples annealed at temperatures exceeding 200°C. When determining the differential cross sections for inelastic electron scattering, the difference between the energy losses in the surface sample layers and the homogeneous bulk located far from the surface is taken into account. The obtained spectra are compared with those of multilayer graphene and pyrolytic graphite. It is shown that the analysis of graphene oxide using X-ray photoelectron spectroscopy gives a picture on a nanometer scale. The obtained data can differ noticeably from the Raman spectroscopy data corresponding to the millimeter scale. [ABSTRACT FROM AUTHOR]

The results of the analysis of carbon-containing materials are presented based on an analysis of the peaks of X-ray photoelectron spectroscopy (XPS) formed by the electrons leaving the analyzed sample in a vacuum without energy loss (peak shape analysis, PSA) and based on the interpretation of the widest possible area of energy loss adjacent to the photoelectron spectroscopy (PES) peak. It is shown that the PES analysis of diamond-like materials containing alloying additives, the concentration of which is comparable with the concentration of carbon, is not effective. The PES analysis of graphene oxide samples that were heat-treated to remove oxygen gave detailed information about the laws of the energy loss of photoelectrons emitted from the 1s level, which determines the allotropic variety of carbon. [ABSTRACT FROM AUTHOR]

The relative concentration of deuterium implanted into a beryllium sample is determined by elastic peak electron spectroscopy (EPES). The method of partial intensities based on solution of the boundary value problem for the transport equation by the invariant embedding method is used for subsequent determination of the energy spectra of reflected electrons. The differential inverse inelastic mean free paths (DIIMFPs) and the differential surface excitation probability (DSEP) are retrieved using a fitting procedure based on numerous solutions of the direct problem with fitting parameters. The high efficiency of the fitting procedure is based on the technique of numerical solution of equations for the partial intensities, which combines precision and a record-high calculation speed. In the work DIIMFP and DSEP are obtained for both the surface region and for a homogeneous array in the bulk. Calculations of DIIMFP and DSEP are carried out for pure beryllium and for beryllium samples implanted with deuterium. The relative concentrations of deuterium into beryllium were determined at a different fluence. The obtained values of the relative deuterium concentrations are nD/nBe = 0.12 ± 0.02 and 0.15 ± 0.03 for an irradiation dose of 5.5 × 1021 and 20.1 × 1021 m–2, respectively. The results indicate that, in comparison with the methods used earlier, the developed method allows an order of magnitude in of the sensitivity of determining the relative hydrogen-isotope concentration in compounds to be attained. [ABSTRACT FROM AUTHOR]

Abstract—: Nondestructive depth profiling method based on reflected electron spectroscopy is presented. Large loss spectra of wide energy range is analyzed. Spectra analysis is performed using two approaches: boundary problem solution using invariant imbedding method and approximate interpretation based on Straight Line Approximation with correction coefficients, which depend on ration of evaporated layer thickness and transport mean free path. It is shown that the transport mean free path, not the inelastic mean free path, limits the information depth of the method in opposite of X-ray photoelectron spectroscopy, elastic peak electron spectroscopy. This fact significantly increase depths that can be analyzed using presented method. Thickness of the evaporated Nb layer on the Si substrate is determined. [ABSTRACT FROM AUTHOR]