Hostname: page-component-cd9895bd7-gxg78 Total loading time: 0 Render date: 2024-12-24T19:00:27.608Z Has data issue: false hasContentIssue false
  • English
  • Français

Computer Programs for Standardless Quantitative Analysis of Minerals Using the Full Powder Diffraction Profile

Published online by Cambridge University Press:  10 January 2013

J. C. Taylor
J. C. Taylor
Affiliation:
CSIRO, Division of Fuel Technology, PMB 7, Menai, NSW 2234, Australia
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

A Fortran 77 computer program has been developed for the quantitative analysis of minerals by multiphase profile analysis of the complete powder diffraction pattern. Featured are full-matrix least-squares refinement of 14 Rietveld “instrumental parameters” (phase scales, asymmetry, preferred orientations (March model), linewidths, instrument zero, lineshapes and unit cell dimensions), Brindley particle absorption contrast factors and amorphicity corrections. The program uses a crystal structure Databank, which contains information on absorption coefficients, unit cell data and crystal structures for some 90 common minerals. New minerals can be easily added. Structure parameters are also refinable by a profile decomposition method using a program called STRUCT. The sum of the calculated patterns, derived from the crystal structure data, is fitted to the observed pattern by a program called TRACSCAL which runs in singlepass multiphase mode and, after the above corrections have been applied, the weight percentages of the component phases are calculated from the Rietveld scaling factors.

The program runs on an IBM-compatible AT computer with 640K of RAM, on an extended memory AT, or a mainframe system. Examples of its use are given with standard mixtures and naturally occurring specimens. On an AT computer with 20MHz clock speed a scaling run, including data input, reading of the pattern, processing of (hkl) files, calculation of the profile and one cycle of least squares fitting takes about 30 seconds for binary standard mixtures and about 2.5 minutes for a 7-phase natural bauxite pattern containing 320 independent (hkl) reflections.

Type
Research Article
Information
Powder Diffraction , Volume 6 , Issue 1 , March 1991 , pp. 2 - 9
Copyright
Copyright © Cambridge University Press 1991

References

Bish, D.L. & Howard, S.A. (1988). J. Appl. Crystallogr., 21, 86–91CrossRefGoogle Scholar
Brindley, G.W. (1945). Phil. Mag., 36, 347–369CrossRefGoogle Scholar
Dollase, W.A. (1986). J. Appl. Crystallogr., 19, 267–272CrossRefGoogle Scholar
Hall, M.M., Veeraraghavan, V.G., Rubin, H. and Winchell, P.G. (1977). J. Appl. Crystallogr., 10, 66–68.CrossRefGoogle Scholar
Hamilton, W.C. (1964). Statistics in Physical Science, Ronald Press, New YorkGoogle Scholar
Hewat, A.W. (1973). Harwell Report 73/239 and Ill. Report 74/ H625.Google Scholar
Hill, R.J. & Howard, C.J. (1986). AAEC Report M112, Lucas Heights Research Laboratories, Menai, NSW Australia.Google Scholar
Hill, R.J. & Howard, C.J. (1987). J. Appl. Crystallogr., 20, 467–474.Google Scholar
Howard, C.J., Hill, R.J. & Sufi, M.A.M. (1988). Chemistry in Australia, 55, 367–369.Google Scholar
Klug, H.P. & Alexander, L.E. (1974). X-Ray Diffraction Procedures for Polycrystalline and Amorphous Materials. New York: Wiley and Sons.Google Scholar
Nuffield, E.W. (1966). X-Ray Diffraction Methods. New York: Wiley and Sons.Google Scholar
Rietveld, H.M. (1969). J. Appl. Crystallogr., 2, 65–71.CrossRefGoogle Scholar
Sheldrick, G. (1976) Shelx-76 program system, University of Cambridge.Google Scholar
Smith, D.K., Johnson, G.G., Scheible, A., Winis, A.M., Johnson, J.L., & Ullman, G. (1987). Pow. Diff., 2, 73–77.Google Scholar
Taylor, A. (1961). X-Ray Metallography, Wiley: New York, p.259–263 and Table 76.Google Scholar
Taylor, J.C. (1978). Report AAEC/E436, Lucas Heights Research Laboratories, Menai, NSW, Australia.Google Scholar
Taylor, J.C. (1980) Report AAEC/E488, Lucas Heights Research Laboratories, Menai, NSW, Australia.Google Scholar
Taylor, J.C. (1987a) Zeolites, 7, 311–318.CrossRefGoogle Scholar
Taylor, J.C. (1987b) Z. Krist, 181, 151–160.CrossRefGoogle Scholar
Taylor, J.C., Kelly, J.W. & Downer, B. (1972). J. Solid State Chem., 5, 291–299.CrossRefGoogle Scholar
Taylor, J.C. & Matulis, C.E. (1990). J. Appl. Crystallogr., submitted.Google Scholar
Taylor, J.C., Miller, S.A., & Bibby, D.M. (1986). Z. Krist., 176, 183–192.Google Scholar
Toraya, H., Yoshimura, M., & Sorriya, S. (1984). J. Amer. Ceram. Soc., 67, C119–C121.CrossRefGoogle Scholar
Wilchinsky, Z.W. (1951). Acta Cryst., 4, 1–9.CrossRefGoogle Scholar
Wiles, D.B., & Young, R.A. (1981) J. Appl. Crystallogr., 14, 149–151.CrossRefGoogle Scholar
Will, G., Parrish, W., & Huang, T.C. (1983). J. Appl. Crystallogr., 26, 611–622.CrossRefGoogle Scholar
de Wolff, P.M. (1947). Physica, 13, 62.CrossRefGoogle Scholar