Soft X-ray absorption and EXAFS on the K edge of aluminium

The authors report EXAFS (extended X-ray absorption fine structure) measurements performed in the 1000-2500 eV range using synchrotron radiation delivered by the ACO storage ring (LURE). The K edge EXAFS spectra of Al in elemental aluminium and alpha alumina have been analysed; it is shown that accurate measurements of the first-neighbour distances are possible even for low-Z atoms. In the case of the metal, the authors emphasise the importance of the screening of the core hole potential in the first 150 eV part of the spectrum.