Sample Thickness and Quantitative Concentration Measurements in XANES Spectroscopy
Alessandra C. Leri, Bruce Ravel
While XANES spectroscopy is an established tool for quantitative information on chemical structure and speciation, elemental concentrations are generally quantified by other methods. The edge step in XANES spectra represents the absolute amount of the measured element in the sample, but matrix effects and sample thickness complicate the extraction of accurate concentrations from XANES measurements, particularly at hard X-ray energies where the X-ray beam penetrates deeply into the sample. XANES has been shown to be a viable method for measuring absolute concentrations of elements in the tender X-ray region with careful standardization. The present study demonstrates the feasibility of XANES spectroscopy in the hard X-ray region as a quantitative tool with a detection limit approaching 1 mg/kg. We assess the effects of sample thickness on edge steps at the Br K-edge and develop a correction factor for use with samples of variable mass. This extends the utility of XANES spectroscopy for quantitative concentration measurements of elements with hard X-ray absorption edges.
and Ravel, B.
Sample Thickness and Quantitative Concentration Measurements in XANES Spectroscopy, Journal of Synchrotron Radiation, [online], https://doi.org/10.1107/S1600577514001283
(Accessed September 30, 2023)