High-energy X-ray absorption spectroscopy at ESRF BM29

The availability of third generation synchrotron sources now allows the rou tine performance of EXAFS investigations using K absorption edges occurring above 30 keV. Measurements made at absorption edges in the energy range 40 keV to 70 keV using the EXAFS beamline BM 29 of the ESRF have demonstrated a great potential for high resolution structural studies. The effect of th e core-hole lifetime broadening, though apparent, is found to be manageable if high quality data are acquired over the large L-range accessible for he avy element K absorption edges. Examples are presented for the Eu ii-edge a nd the W K-edge, demonstrating clear advantages for structural investigatio ns over those conventionally performed at the LIII absorption edge.