Hostname: page-component-586b7cd67f-l7hp2 Total loading time: 0 Render date: 2024-11-26T04:33:50.588Z Has data issue: false hasContentIssue false
  • English
  • Français

New X-Ray Powder Data for Gorceixite, BaAl3(PO4)2(OH)5·H2O, an Evaluation of d-Spacings and Intensities, Pseudosymmetry and Its Influence on the Figure of Merit

Published online by Cambridge University Press:  10 January 2013

Frank N. Blanchard
Frank N. Blanchard
Affiliation:
Department of Geology, University of Florida, Gainesville, Florida 32611, U.S.A.
Get access Rights & Permissions [Opens in a new window]

Abstract

New powder and crystallographic data for gorceixite, a mineral of the crandallite subgroup of the alunite group, are reported and compared with current Powder Data File (PDF) patterns and with calculated patterns. Both d-spacings and intensities have been evaluated, and the results indicate a significant improvement over existing patterns. Indexing of the reflections is given for the true monoclinic symmetry, Cm (8), the pseudorhombohedral symmetry, (166) (to compare with structurally analogous minerals), and the pseudocubic symmetry, Fm3m (225). Because of the strong pseudosymmetry, the overall figure of merit is lower than would be the case for indexing in one of the pseudospace groups.

Type
Research Article
Information
Powder Diffraction , Volume 4 , Issue 4 , December 1989 , pp. 227 - 230
Copyright
Copyright © Cambridge University Press 1989

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

Appleman, D. E. & Evans, H. T. Jr., (1973). Report PB216188. U. S. Dept. of Commerce, National Technical Information Service, 5285 Port Royal Rd., Springfield, VA 22151.Google Scholar
Blanchard, F. N. and Palenik, G. J. (1989). Pow. Diff. 4, 21–23.CrossRefGoogle Scholar
Blanchard, F. N. (1989). Pow. Diff. 4, 103–105.CrossRefGoogle Scholar
Fleischer, M. (1987). Glossary of Mineral Species. The Mineralogical Record Inc, Tucson, AZ.Google Scholar
Garvey, R. G. (1986). Pow. Diff. 1, 114.Google Scholar
Garvey, R. G. (1988). PDFEAPC. MS-DOS implementation of NBS*AIDS83, obtainable from the JCPDS-ICDD.Google Scholar
McCarthy, G. J. & Welton, J. M. (1989). Pow. Diff., in the press.Google Scholar
Mineral Powder Diffraction File (1986). Eds. Bayliss, P., Erd, D. C., Mrose, M. E., Sabina, A. P. & Smith, D. K.. Swarthmore, PA: International Centre for Diffraction Data.Google Scholar
NBS SRM-640 (1974). Silicon Powder X-ray Diffraction Standard. Obtainable from the National Institute of Standards and Technology, Office of Standard Reference Materials, Gaithcrsburg, MD 20899.Google Scholar
Powder Diffraction File, 1988. Swarthmore, PA: International Centre for Diffraction Data.Google Scholar
Radoslovich, E. W. & Slade, P. G. (1980). Neues Jahrb. Mineral., Monatsh., 157–170.Google Scholar
Radoslovich, E. W. (1982). Neues Jahrb. Mineral. Monatsh., 446–464.Google Scholar
Palache, C., Berman, H. & Frondel, C. (1951). A System of Mineralogy, 7th ed., Vol 2. (Dana, J. D.). J. Wiley & Sons, New York.Google Scholar
Smith, G. S. & Snyder, R. L. (1979). J. Appl. Crystallogr. 12, 60–65.CrossRefGoogle Scholar
Smith, D. K. & Smith, K. L. (1987). MICRO-POWD, Materials Data, Inc., Livermore, CA.Google Scholar