engleski

Chemical effects on the Kα X-ray lines of Ti and Cr compounds induced by MeV protons and comparison with Kβ lines

Recently we measured high resolution Kβ spectra of 3d metals and their selected compounds using 2 MeV proton beams. The results [1-4] showed that high resolution Kβ PIXE spectroscopy is sensitive to chemical effects and that deviations between X-ray energies and intensities can be correlated with structural characteristics of investigated compounds, like metal oxidation state, type of ligand (C, O, N, F), and average metal-ligand bond lengths. However, intensities of Kβ components of K X-ray spectra are low when compared with Kα components, which limits possibilities for practical applications of the Kβ HR-PIXE spectroscopy (i.e. increases the measuring times or beam current on a target that can in some cases introduce chemical changes within the target). Therefore in this work we measured high resolution Kα X-ray spectra of selected Ti and Cr compounds using 2 MeV protons. The measured spectra were analysed in order to extract X-ray energies and intensities of main individual components, including Kα diagram lines (Kα1, Kα2) and KL1 satellite peaks (Kα3, Kα4). The results have been compared with the results of previous studies and with results of ab-initio quantum chemical calculation based on density functional theory (DFT). Possibilities for chemical speciation have been discussed and compared with the capabilities of the Kβ HR-PIXE spectroscopy.

high resolution x-rays ; chemical effects ; PIXE

nije evidentirano