The fluorescence yields of the three L-subshells of bismuth were also determined using a reflection geometry setup. Mass attenuation coefficients of bismuth were determined experimentally in the photon energy range from 100 eV to 30 keV by using monochromatized synchrotron radiation at SOLEIL (France). However reliable measurements are not so many illustrating the inherent difficulties. Some review articles present compilations of measured fluorescence yields values found in the literature. However, they significantly differ for low photon energies and around the absorption edges of the elements. These compilations are most often in good agreement for photon energies in the hard x-ray ranges. For example, several databases giving the mass attenuation coefficients are accessible and frequently used within a large community of users. The knowledge of atomic fundamental parameters such as the mass attenuation coefficients or fluorescence yields with low uncertainties, is of decisive importance in elemental quantification involving x-ray fluorescence analysis techniques. This paper focuses on the model and parameters for fluorescence. There is a cost in preparation and measurement time of less than a factor of two, and the principles are clear and can be routinely implemented on any beamline. This enables high‐accuracy data and theoretical and experimental analysis to below 0.03% accuracy. The standard error from the dispersion and variance was reduced by up to 50.5% after the correction for the 50 μm sample. The resulting correction is most significant for thicker foils with the 50 μm sample experiencing a shift in attenuation of up to 15.5% for the largest aperture while the 25 and 10 μm samples saw corrections of up to 0.153 and 0.00639% respectively. The model theory fits the experimental measurements well. A significant background scattering due to zinc fluorescence from the beamline optics was identified and treated for the first time. Correction for this systematic is important for absolute measurement, for edge‐jump and edge characterization, and for near‐edge structure and amplitudes. The correction is energy‐dependent and sample thickness‐dependent and changes the structure and relative amplitudes of oscillations in the near‐edge region. In this work, fluorescence has a large impact on the attenuation measurements of thick zinc foils. Comparison of attenuation measurements produced with different aperture combination permit investigation of the effect of fluorescence radiation. The experimental setup includes different sized apertures to control the number of secondary X‐rays entering the detector. We use the X‐ray extended range technique‐like method (XERT‐like). We present a method to explore the effect of fluorescence on X‐ray attenuation measurements obtained from X‐ray absorption spectroscopy (XAS). Bond length uncertainties are of the order of 20–40 fm. Accuracies achieved, when compared with the literature, exceed those achieved by both relative and differential XAFS, and represent a state-of-the-art for future structural investigations. This work investigates crystal dynamics, nanostructural evolution and the results of using the Debye and Einstein models to determine atomic positions. The XAFS spectra are analysed using eFEFFIT to provide a robust measurement of the evolution of nanostructure, including such properties as net thermal expansion and mean-square relative displacement. A recent method for modelling self-absorption in fluorescence has been adapted and applied to a solid sample. The measured transmission and fluorescence XAFS spectra are compared and benchmarked against each other with detailed systematic analyses. This is also the first hybrid-like experiment at the Australian Synchrotron. This is the first time transition metal X-ray absorption fine structure (XAFS) has been studied using the hybrid technique and at low temperatures. The most accurate measurements of the mass attenuation coefficient for metals at low temperature for the zinc K -edge from 9.5 keV to 11.5 keV at temperatures of 10 K, 50 K, 100 K and 150 K using the hybrid technique are reported.
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