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Quantitative phase analysis of challenging samples using neutron powder diffraction. Sample #4 from the CPD QPA round robin revisited

Published online by Cambridge University Press:  29 April 2016

Pamela S. Whitfield
Pamela S. Whitfield*
Affiliation:
Oak Ridge National Lab, Spallation Neutron Source, PO Box 2008, MS-6475, Oak Ridge, Tennessee 37831
*
a)Author to whom correspondence should be addressed. Electronic mail: [email protected]
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Abstract

Quantitative phase analysis (QPA) using neutron powder diffraction more often than not involves non-ambient studies where no sample preparation is possible. The larger samples and penetration of neutrons versus X-rays makes neutron diffraction less susceptible to inhomogeneity and large grain sizes, but most well-characterized QPA standard samples do not have these characteristics. Sample #4 from the International Union of Crystallography Commission on Powder Diffraction QPA round robin was one such sample. Data were collected using the POWGEN time-of-flight (TOF) neutron powder diffractometer and analysed together with historical data from the C2 diffractometer at Chalk River. The presence of magnetic reflections from Fe3O4 (magnetite) in the sample was an additional consideration, and given the frequency at which iron-containing and other magnetic compounds are present during in-operando studies their possible impact on the accuracy of QPA is of interest. Additionally, scattering from thermal diffuse scattering in the high-Q region (<0.6 Å) accessible with TOF data could impact QPA results during least-squares because of the extreme peak overlaps present in this region. Refinement of POWGEN data was largely insensitive to the modification of longer d-spacing reflections by magnetic contributions, but the constant-wavelength data were adversely impacted if the magnetic structure was not included. A robust refinement weighting was found to be effective in reducing quantification errors using the constant-wavelength neutron data both where intensities from magnetic reflections were ignored and included. Results from the TOF data were very sensitive to inadequate modelling of the high-Q (low d-spacing) background using simple polynomials.

Keywords

quantitative phase analysisneutron diffractionmicroabsorption
Type
Technical Articles
Information
Powder Diffraction , Volume 31 , Issue 3 , September 2016 , pp. 192 - 197
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Copyright
Copyright © International Centre for Diffraction Data 2016 

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References

Belov, N. V., Neronova, N. N., and Smirnova, T. S. (1955). “The 1651 Shubnikov groups,” Trudȳ Inst. Kristall. 11, 33–67 (in Russian).Google Scholar
Brindley, G. W. (1945). “The effect of grain and particle size on X-ray reflections from mixed powders and alloys, considered in relation to the quantitative determination of crystalline substances by X-ray methods,” Phil. Mag. 3, 347–369.Google Scholar
Coelho, A. A. (2015). TOPAS, version 6 beta (Computer Software), Coelho Software, Brisbane.Google Scholar
Cox, D. E., Moodenbaugh, A. R., Sleight, A. W., and Chen, H. Y. (1980). “Structural refinement of neutron and X-ray data by the Rietveld method: application to Al2O3 and BiVO4 ,” J. Nat. Bur. Stand. 657, 189–201.Google Scholar
David, W. I. F. (2001). “Robust Rietveld refinement in the presence of impurity phases,” J. Appl. Crystallogr. 34, 691–698.Google Scholar
Finger, L. W. (1973). “Refinement of the crystal structure of zircon,” Carnegie Inst. Wash. Yearbook 72, 544–547.Google Scholar
Fleet, M. E. (1981). “The structure of magnetite,” Acta Crystallogr. B37, 917–920.Google Scholar
Gualtieri, A. F. (2000). “Accuracy of XRD QPA using the combined Rietveld-RIR method,” J. Appl. Crystallogr. 33, 267–278.Google Scholar
Guinier, A. (1956). Theorie et technique de la radiocristallographie (Dunold, Paris).Google Scholar
Hill, R. J. and Howard, C. J. (1987). “Quantitative phase analysis from neutron powder diffraction data using the Rietveld method,” J. Appl. Crystallogr. 31, 47–51.Google Scholar
Huq, A., Hodges, J. P., Gourdon, O., and Heroux, L. (2011). “Powgen: a third generation high-resolution high-throughput powder diffraction instrument at the Spallation Neutron Source,” Z. Kristallogr. Proc. 1, 127–135.Google Scholar
Kisi, E. H. and Howard, C. J. (2008). Applications of Neutron Powder Diffraction (Oxford Science Publications, Oxford).Google Scholar
Larson, A. C. and Von Dreele, R. B. (1994). General Structure Analysis System (GSAS) (Report LAUR 86–748) Los Alamos, New Mexico: Los Alamos National Laboratory.Google Scholar
León-Reina, L., De la Torre, A. G., Porras-Vásquez, M., Cruz, M., Ordonez, L. M., Alcobé, X., Gispert-Guirado, F., Larrañaga-Varga, A., Paul, M., Fuellmann, T., Schmidt, R., and Aranda, M. A. G. (2009). “Round robin on Rietveld quantitative phase analysis of Portland cements,” J. Appl. Crystallogr. 42, 906–916.Google Scholar
Madsen, F. A., Rose, M. C., and Cee, R. (1995). “Review of quartz analytical methodologies: present and future needs,” Appl. Occup. Environ. Hyg. 10, 991–1002.Google Scholar
Madsen, I. C., Scarlett, N. V. Y., Cranswick, L. M. D., and Lwin, T. (2001). “Outcomes of the International Union of Crystallography Commission on powder diffraction round robin on quantitative phase analysis: samples 1a to 1 h,” J. Appl. Crystallogr. 34, 409–426.Google Scholar
Madsen, I. C. and Scarlett, N. V. Y. (2008). “Quantitative phase analysis,” in Powder Diffraction Theory and Practice, edited by Dinnebier, R. E. and Billinge, S. J. L. (Royal Society of Chemistry, London), pp. 298–331.Google Scholar
Omotoso, O., McCarty, D. K., Kleeburg, R., and Hillier, S. (2006). “Some successful approaches to quantitative mineral analysis as revealed by the 3rd Reynold's cup contest,” Clays Clay Miner. 54, 748–760.Google Scholar
Scarlett, N. V. Y., Madsen, I. C., Cranswick, L. M. D., Lwin, T., Groleau, E., Stephenson, G., Aylmore, M., and Agron-Olshina, N. (2002). “Outcomes of the International Union of Crystallography Commission on Powder Diffraction round robin on quantitative phase analysis: samples 2, 3, 4, synthetic bauxite, natural granodiorite and pharmaceuticals,” J. Appl. Crystallogr. 35, 383–400.Google Scholar
Salter, T. L. and Riley, W. E. (1994). “Quartz determination in kaolin at the 0.1% level,” Anal. Chim. Acta. 286, 49–55.Google Scholar
Small, J. A. and Watters, R. L. (2015). Standard Reference Material 1878b. Respirable Alpha Quartz (Certificate of Analysis) Gaithersburg, Maryland: National Institute of Standards and Technology.Google Scholar
Stone, K. H., Lapidus, S. H., and Stephens, P. W. (2009). “Implementation and use of robust refinement in powder diffraction in the presence of impurities,” J. Appl. Cryst. 42, 385–391.Google Scholar
Toby, B. H. (2003). “CIF applications. XII. Inspecting Rietveld fits from pdCIF: pdCIFplot ,” J. Appl. Crystallogr. 36, 1285–1287.Google Scholar
Toraya, H., Hayashi, S., and Nakayasu, T. (1999). “Quantitative phase analysis of α- and β-silicon nitrides. II. Round robins,” J. Appl. Crystallogr. 31, 716–729.Google Scholar
West, A. R. (1984). Solid State Chemistry and its Applications (John Wiley & Sons, Chichester).Google Scholar
Whitfield, P. S. and Mitchell, L. D. (2008). “Phase identification and quantitative methods,” in Principles and Applications of Powder Diffraction, edited by Clearfield, A., Reibenspies, J. and Bhuvanesh, N. (John Wiley & Sons, Chichester), pp. 226–260.Google Scholar
Zevin, L. S. and Kimmel, G. (1995). Quantitative X-Ray Diffractometry (Springer, New York).Google Scholar
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