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Performing an x-ray scattering analysis can underpin the quantitative description of a sample of interest, for example, to complement an x-ray fluorescence analysis. However, the reliability of such an analytical approach depends on good knowledge of scattering coefficients (or scattering cross-sections), which describe the probability of interaction and are characteristic of each chemical element. In this work, a metrological study of experimentally determining differential Rayleigh and Compton scattering coefficients for nickel is presented. Angular scans of the scattering intensities at different positions are enabled by a flexible experimental set-up and, therefore, allow for the robust determination of differential scattering coefficients at a wide range of forward and backward scattering angles. As a result, scattering coefficients in the range from 0.117 ( 14 ) × 10 − 3 cm2 g−1 sr−1 to 33.7 ( 39 ) × 10 − 3 cm2 g−1 sr−1 were determined in the momentum transfer range of 12.1 nm−1 to 22.4 nm−1. In addition, utilizing monochromatized and highly linearly polarized synchrotron radiation ( E 0 = 30 keV ) ensures direct comparability to theoretical databases.

A reliable and quantitative material analysis is crucial for assessing new technological processes, especially to facilitate a quantitative understanding of advanced material properties at the nanoscale. To this end, X‐ray fluorescence microscopy techniques can offer an element‐sensitive and non‐destructive tool for the investigation of a wide range of nanotechnological materials. Since X‐ray radiation provides information depths of up to the microscale, even stratified or buried arrangements are easily accessible without invasive sample preparation. However, in terms of the quantification capabilities, these approaches are usually restricted to a qualitative or semi‐quantitative analysis at the nanoscale. Relying on comparable reference nanomaterials is often not straightforward or impossible because the development of innovative nanomaterials has proven to be more fast‐paced than any development process for appropriate reference materials. The present work corroborates that a traceable quantification of individual nanoobjects can be realized by means of an X‐ray fluorescence microscope when utilizing rather conventional but well‐calibrated instrumentation instead of reference materials. As a proof of concept, the total number of atoms forming a germanium nanoobject is quantified using soft X‐ray radiation. Furthermore, complementary dimensional parameters of such objects are reconstructed.

X-ray fluorescence (XRF) analysis is a widely applied technique for the quantitative analysis of thin films up to the $\mu$m scale because of its non-destructive nature and because it is easily automated. When low uncertainties of the analytical results in the few percent range are required, the non-linear secondary fluorescence effect in multi-elemental samples may complicate an otherwise straightforward quantification, since it can easily exceed a relative contribution of 20%. The conventional solution, to rely on good performing reference samples, is hindered by their low availability, especially for thin film applications. To address this challenge, we demonstrate a flexible production method of multilayered, alloyed thin films with significant secondary fluorescence contributions. We use reference-free XRF analysis to validate the reliability of the physical model for secondary fluorescence, which includes a thorough uncertainty estimation. The investigated specimens are being qualified as calibration samples for XRF or other quantitative analyses.

We present experimental and theoretical X-ray emission spectroscopy (XES) data of the Fe Kβ line for Iron(II)sulfide (FeS) and Iron(II)disulfide (FeS(2)). In comparison to X-ray absorption spectroscopy (XAS), XES offers different discrimination capabilities for chemical speciation, depending on the valence states of the compounds probed and, more importantly in view of a a broader, laboratory-based use, a larger flexibility with respect to the excitation source used. The experimental Fe Kβ XES data was measured using polychromatic X-ray radiation and a compact full-cylinder von Hamos spectrometer while the calculations were realized using the OCEAN code. The von Hamos spectrometer used is characterized by an energy window of up to 700 eV and a spectral resolving power of E/ΔE = 800. The large energy window at a single position of the spectrometer components is made profit of to circumvent the instrumental sensitivity of wavelength-dispersive spectrometers to sample positioning. This results in a robust energy scale which is used to compare experimental data with ab initio valence-to-core calculations, which are carried out using the ocean package. To validate the reliability of the ocean package for the two sample systems, near edge X-ray absorption fine structure measurements of the Fe K absorption edge are compared to theory using the same input parameters as in the case of the X-ray emission calculations. Based on the example of iron sulfide compounds, the combination of XES experiments and ocean calculations allows unravelling the electronic structure of different transition metal sulfides and qualifying XES investigations for the speciation of different compounds.

In this work the complete L-emission spectrum of gadolinium with respect to line energies, natural line widths, and relative transition probabilities was investigated using monochromatized synchrotron radiation. The measurements were realized in the PTB laboratory at BESSY II by means of an in-house built von Hamos spectrometer based on up to two full-cylinder HAPG mosaic crystal. The von Hamos spectrometer is calibrated by means of elastically scattered photons from the employed synchrotron radiation beamline leading to a well-defined energy scale and an experimentally determined spectrometer response. A selective excitation of the gadolinium L subshells was carried out to ensure a robust deconvolution of neighboring emission lines of different L subshells. The experimental results are discussed in the context of existing data from common databases and published values since significant deviations, especially for the L$\gamma_2$ and L$\gamma_3$ emission lines, are observed. We further substantiate and discuss two satellite lines at the low-energy side of the L$\beta_{2,15}$ and L$\gamma_1$ emission lines arising from the N$_{4,5}$ subshell.