Hostname: page-component-76fb5796d-5g6vh Total loading time: 0 Render date: 2024-04-28T12:19:21.158Z Has data issue: false hasContentIssue false

Simultaneous Use of Observed and Calculated Standard Profiles in Quantitative XRD Analysis of Minerals by the Multiphase Rietveld Method: The Determination of Pseudorutile in Mineral Sands Products

Published online by Cambridge University Press:  10 January 2013

J.C. Taylor
Affiliation:
CSIRO, Division of Coal and Energy Technology, Lucas Heights Research Laboratories, PMB 7, Menai, NSW, 2234, Australia
Zhu Rui
Affiliation:
Julius Kruttschnitt Mineral Research Centre, Isles Rd., Indooroopilly, Queensland, 4068, Australia

Abstract

In conventional multiphase Rietveld refinement, now being used for quantitative phase determination, the crystal structure of each phase needs to be known in order to generate a calculated standard pattern of the phase to be refined against the measured XRD pattern. This is a disadvantage when the structural data for a phase are imperfect or unknown and may prevent an analysis.

A method is given whereby a phase with an imperfectly known or unknown crystal structure can be included in a multiphase Rietveld refinement, with other well-characterised phases, by use of an empirical or “observed” hkl file for that phase, with the SIROQUANT software package. The amplitudes 1F(hkl)1 in the empirical hkl file of the phase generate a reference profile for it which agrees with a measured standard pattern of the phase. Methods are given for the creation and scaling of empirical or “observed” phase hkl datasets. The Rietveld variable parameters (preferred orientation, linewidth, lineshape and unit cell) are refinable in the usual way for a phase with an empirical hkl dataset.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1992

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Bish, D.L. & Howard, S.A. (1988). J. Appl. Crystallogr. 21, 8691.CrossRefGoogle Scholar
Brindley, G.W. (1945). Phil Mag. 36, 347369.CrossRefGoogle Scholar
Dollase, W.A. (1986). J. Appl. Crystallogr. 19, 267272.CrossRefGoogle Scholar
Grey, I.E. & Reid, A.F. (1975). Am. Miner. 60, 898906.Google Scholar
Heinrich, E.W. (1965). Microscopic Identification of Minerals, McGraw Hill, New York.Google Scholar
Hewat, A.W. (1973). Harwell Report No. 73/239, and ILL Report No. 74/ H 625.Google Scholar
Hill, R.J. & Howard, C.J. (1987). J. Appl. Crystallogr. 20, 467474.CrossRefGoogle Scholar
Klug, H.P. & Alexander, L.E. (1974). X-Ray Diffraction Procedures, p 656, John Wiley and Sons, New York.Google Scholar
Matulis, C.E. & Taylor, J.C. (1992). Pow. Diff. 7, 8994.CrossRefGoogle Scholar
O'Connor, B.H. & Raven, M.D. (1988). Pow. Diff. 3, 26.CrossRefGoogle Scholar
O'Connor, B.H., Deyu, Li, Jordan, B.Raven, M.D. & Fazey, P.G. (1990). Advances in X-Ray Analysis 33, 269275.CrossRefGoogle Scholar
Rietveld, H.M. (1969). J. Appl. Crystallogr. 2, 6571.CrossRefGoogle Scholar
Smith, D.K., Johnson, G.G.Schieble, A., Wims, A. M., Johnson, J.L. & Ullman, G. (1987). Pow. Diff. 2, 7377.CrossRefGoogle Scholar
Taylor, J.C. (1991). Pow. Diff. 6, 29.CrossRefGoogle Scholar
Taylor, J.C. & Matulis, C.E. (1991). J. Appl. Crystallogr. 24, 1417.CrossRefGoogle Scholar
Werner, P.-E., Salome, S., Malmros, G. & Thomas, J.O. (1979). J. Appl. Crystallogr. 12, 107109.CrossRefGoogle Scholar
Wiles, D.B. & Young, R.A. (1981). J. Appl. Crystallogr. 14, 149151.CrossRefGoogle Scholar
Wilson, A.J.C. (1942). Nature 150, 152.CrossRefGoogle Scholar