PDF from X-ray powder diffraction for nanometer-scale atomic structure analysis of quasicrystalline alloys

Abstract

Abstract For three icosahedral alloys in the Mg—Zn-RE(RE = Ho, Y) systems, the atomic pair distribution functions (PDFs) have been obtained from sealed X-ray tube (in-house) and synchrotron (ESRF and APS) powder diffraction experiments. The PDFs are at least qualitatively comparable and are suitable for least squares r ≈ 2 nm local structure refinements. A recent local model for si-Ho—Mg—Zn from in-house data can be confirmed using the synchrotron data. Acquisition and the quality of the data from the different sources are discussed. The better resolved synchrotron data open perspectives for larger scale and thus more detailed models.