Obtaining 2D-Images of Local Atomic Environments at μm level through Resonant Inelastic X-ray Scattering (RIXS)

JUAN JOSÉ LEANI; JOSE ROBLEDO; H.J. SÁNCHEZ

Brescia

Congreso; International Conference on Total Reflection X-Ray Fluorescence Analysis and Related Methods (TXRF2017).; 2017

Recently it was demonstrated that, by means of the inspection of the fine structure of the RIXS emission peak, the chemical state of an element can be determined [1,2]. One of the most important characteristics of RIXS, using SDD systems with low-resolution in energy, is the possibility to combine it with all of the experimental techniques and geometries associated to X-Ray Fluorescence spectrometry. Hence, combinations of total reflection or depth profiling analysis using grazing incidence geometries and confocal setups have been reported [3-8]. The possibility of combining high-resolution spatially resolved XRF with RIXS is, nowadays, quite open. Using these facts, we performed 2D-RIXS maps in different samples of interest. The measurements were carried out at the XRF beamline @ Brazilian Synchrotron Light Laboratory. The samples were irradiated with photons having a fixed monochromatic energy below the K absorption edge of the elements of interest. After a simple data processing, the fine structure of the RIXS spectra show oscillation patterns that depend on the different compounds of each element. This outcome was verified by using a complementary Principal Component Analysis (PCA).The analyzed samples, of high importance in environmental and material science, are relevant since they present a rich contrast of compounds of the same elements, being difficult to analyze using conventional time-consuming spectroscopic techniques. Using this new RIXS tool, we were able to produced fast and reliable maps/images showing the different chemical environments/compounds of the elements of interest, providing atomic environment information at micrometer level in a 2D regime.Examples of applications of this novel tool for chemical state determinations in 2D are presented and discussed.