Rietveld Refinement using Synchrotron X-ray Powder Diffraction Data Collected in Transmission Geometry using an Imaging-Plate Detector: Application to Standardm-ZrO₂

Abstract

The results of Rietveld refinements using synchrotron X-ray powder diffraction data collected in transmission mode with a new flat imaging-plate (IP) technique agree with those obtained from other techniques, m-ZrO2 was chosen as test compound because it was the standard selected by the Commission on Powder Diffraction of the International Union of Crystallography for a round robin of Rietveld refinement using data obtained by different techniques and from different laboratories [Hill & Cranswick (1994). J. Appl. Cryst. 27, 802-844]. For comparison, new data were also collected using a gas-filled position-sensitive detector. Powder diffraction using a flat IP detector requires a modification to the geometric term of the Lorentz factor and the zero-shift correction. Other factors that were accurately taken into account are the polarization of the synchrotron beam, the angle-dependent variations induced by the use of a flat detector and the absorption.

Blue emission of ZrO2:Tm nanocrystals with different crystal structure under UV excitation

“…This phenomenon may be responsible for the phase transition. When the host structure transform from m-ZrO 2 to t-ZrO 2 , not only the number of Tm 3+ ions in the unit cell increases but also the volume of unit cell decreases quickly, 140.54 Å 3 for m-ZrO 2 [13] and 69.08 Å 3 for t-ZrO 2 [14]. Both changes can induce the shortening of the distance of Tm 3+ -Tm 3+ effectively.…”

Variable incidence angle – X-ray absorption spectroscopy for the study of Zircaloy corrosion layers

“…Both XANES and EXAFS results are discussed in a comparative way in this Section using current [13]. At the zirconium K-edge energy, the X-ray beam may pass through the zirconia film, then into the Zircaloy matrix, the later contributing to the fluorescence intensity.…”

Heterocoagulation-spray drying process for the inclusion of ceramic pigments

“…1) in order to evaluate the chemical inertia of ZrO 2 towards hematite. 25,26 Starting atomic parameters for zirconia were taken from Gualtieri et al, 27 considering P2 1 /c as the space group. Depending upon the number of impurities up to 35 independent variables were refined: zero-point, 10 coefficients of the shifted Chebyschev function to fit the background, scale factor and cell dimensions of hematite (the only accessory phase), scale factor, cell dimensions, atomic positions, site occupancies, isotropic displacement parameters of zirconia, profile coefficients -1 Gaussian (GW) and 2 lorentzian terms (LX, LY) -for both phases.…”