  Even though, the crystal structure of the intermediate (S') and the
equilibrium S (Al2CuMg) phase were subject of many investigations by using
mostly imaging or diffraction techniques, the results remain still
controversial. In this study, we used X-ray absorption spectroscopy (XAFS) to
verify the correct structure considering the well-known models reported by
Perlitz & Westgren (PW), Mondolfo, Radmilovic & Kilaas and Yan et al. The
structure was confirmed by direct comparison to simulated XAFS spectra using
the software tool FDMNES. Our results support the widely accepted PW model as
the correct structure while other models do not match our observations.
