The beamline "LUCIA" (Line for Ultimate Characterisation by Imaging and Absorption) is a "tender" (0.8-8 keV) X-ray microprobe with capabilities for chemical speciation by x-ray absorption spectroscopy ( µ XAS) and for elemental mapping by x-ray micro-fluorescence ( µ XRF). It allows the possibility to measure heterogeneous samples at a micronic size and to combine these two element-specific and non-destructive techniques.
A monochromatic beam of µm size is incident on a sample which is carried on a scanning x-z stage. µ XRF shows the location of the elements, their relative abundances, and with which other elements they are associated. One can take advantage of the monochromatic beam which allows to separate out different elements by their absorption edges. After a cartography of the sample by fluorescence, interesting spots can be analyzed by XAS to determine the speciation (local chemistry, quantitative determination of the local geometric structure around the absorbing atom) of the elements and how this depends on the different components.
µ XRF and µ XAS can be combined with other microtechniques like Raman spectroscopy to give complementary informations on the sample. The energy range offered by the beamline corresponds to the best performances of SLS and SOLEIL in terms of brilliance. It allows XAS experiments at the K edge of elements from Na to Fe, L edges from Ni to Gd, and M edges of rare earths and actinides.
