Hostname: page-component-78c5997874-8bhkd Total loading time: 0 Render date: 2024-11-13T04:10:10.987Z Has data issue: false hasContentIssue false
  • English
  • Français

X-ray powder diffraction data and Rietveld refinement for Ln6WO12 (Ln=Y, Ho)

Published online by Cambridge University Press:  10 January 2013

N. Diot ,
P. Bénard-Rocherullé  and
R. Marchand
N. Diot
Affiliation:
Laboratoire “Verres et Céramiques,” UMR CNRS 6512, Université de Rennes 1, Campus de Beaulieu, 35042 Rennes Cedex, France
P. Bénard-Rocherullé*
Affiliation:
Laboratoire “Chimie du Solide et Inorganique Moléculaire,” UMR CNRS 6511, Université de Rennes 1, Campus de Beaulieu, 35042 Rennes Cedex, France
R. Marchand
Affiliation:
Laboratoire “Verres et Céramiques,” UMR CNRS 6512, Université de Rennes 1, Campus de Beaulieu, 35042 Rennes Cedex, France
*
a)Author to whom correspondence should be addressed; electronic mail: patricia.benard@univ-rennes.fr
Get access Rights & Permissions [Opens in a new window]

Abstract

The crystal structure of the two isostructural rare earth tungstates Ln6WO12 (Ln=Y, Ho) has been refined by the Rietveld method from X-ray powder diffraction data. They crystallize with a three-dimensional rhombohedral structure (S.G. R3¯ and Z=3 for the R-centered setting) closely related to that of the binary oxides Ln7O12 and deriving from the ideal fluorite structure. Final refinements, with isotropic thermal motion for each atom, resulted in profile and structure factors Rwp=0.166, RF=0.037 with Ln=Y and Rwp=0.121, RF=0.040 with Ln=Ho. The rare earth element is sevenfold coordinated with Ln–O bond lengths ranging from 2.19 to 2.70 Å for Y6WO12 and from 2.18 to 2.68 Å for Ho6WO12; the coordination polyhedron may be described as a monocapped trigonal prism. The tungsten atom is located at the center of a WO6 octahedron with a unique W–O distance of 1.98 and 1.92 Å for Y6WO12 and Ho6WO12, respectively.

Keywords

rare earth tungstatesLn7O12 rare earth binary oxidesdefect fluorite structureX-ray powder diffractionRietveld refinement
Type
Technical Articles
Information
Powder Diffraction , Volume 15 , Issue 4 , December 2000 , pp. 220 - 226
Copyright
Copyright © Cambridge University Press 2000

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

Aitken, E. A., Bartram, S. K., and Juenke, E. F. (1964). “Crystal chemistry of the rhombohedral MO 3.3R 2O 3 compounds,” Inorg. Chem. 3, 949–954.CrossRefGoogle Scholar
Bartram, S. F. (1966). “Crystal structure of the rhombohedral MO 3.3R 2O 3 compounds (M=U, W or Mo) and their relation to ordered R 7O 12 phases,” Inorg. Chem. 5, 749–754.CrossRefGoogle Scholar
Beaury, O., Faucher, M., and Caro, P. (1978). “Crystal structure and fluorescence spectrum of 3Y 2O 3, WO 3:Eu 3+,”Mater. Res. Bull. 13, 175–185.CrossRefGoogle Scholar
Bénard, P., Louër, D., Dacheux, N., Brandel, V., and Genet, M. (1994). “U(UO 2)(PO 4)2, a new mixed-valence uranium orthophosphate: Ab initio structure determination from powder diffraction data and optical and X-ray photoelectron spectra,” Chem. Mater. 6, 1049–1058.CrossRefGoogle Scholar
Bevan, D. J. M., and Drennan, J. (1982). “Structure determination of the fluorite-related superstructure phases Er 10W 2O 21 and Y 10W 2O 21,” Acta Crystallogr., Sect. B: Struct. Crystallogr. Cryst. Chem. B38, 2991–2997.Google Scholar
Borchardt, H. J. (1963). “Yttrium tungsten oxides,” Inorg. Chem. 2, 170–173.Google Scholar
Boultif, A., and Louër, D. (1991). “Indexing of powder diffraction patterns for low symmetry lattices by the successive dichotomy method,” J. Appl. Crystallogr. 21, 987–993.CrossRefGoogle Scholar
Chang, L. L. Y., and Philipps, B. (1964). “Samarium and lanthanum tungstates of the 3R 2O 3.WO 3 type,” Inorg. Chem. 3, 1792–1794.Google Scholar
Chang, L. L. Y., Scroger, M. G., and Philipps, B. (1966). “High temperature phase equilibria in the systems Sm 2O 3-WO 3 and Sm 2O 3-W-WO 3,”J. Inorg. Nucl. Chem. 28, 1179–1184.CrossRefGoogle Scholar
Cotton, F. A., and Legzdins, P. (1968). “An example of the monocapped octahedral form of heptocoordination. The crystal and molecular structure of tris (1-phenyl-1,3-butanedionato) aquajtrium (III),” Inorg. Chem. 7, 1977–1783.CrossRefGoogle Scholar
Cunningham, J. A., Sands, D. E., Wagner, W. F., and Richardson, M. F. (1969). “The crystal and molecular structure of ytterbium acetylacetonate monohydrate,” Inorg. Chem. 8, 22–28.CrossRefGoogle Scholar
De Wolff, P. M. (1968). “A simplified criterion for the reliability of a powder pattern indexing,” J. Appl. Crystallogr. 12, 60–65.Google Scholar
DIFFRAC-AT, Version V3.3 (1993). PROFILE user's guide from Socabim, Siemens Analytical X-rays Systems, Inc., Karlsruhe, Germany.Google Scholar
Hartmann, T., Ehrenberg, H., Miehe, G., and Fuess, H. (1999). “Preparation and characterization of rare earth rhenium oxides Ln 6ReO 12, Ln=Ho, Er, Tm, Yb, Lu,” J. Solid State Chem. 148, 220–223.Google Scholar
International Centre for Diffraction Data, PDF database, Newtwon Square, PA, USA.Google Scholar
Kang, Z. C., and Eyring, L. (1988). “The sovolytic disproportionation of mixed-valence compounds. I. Pr 7O 12,”J. Solid State Chem. 75, 52–59.CrossRefGoogle Scholar
Kuribayashi, K., Yoshimura, M., Ohta, T., and Sata, T. (1980). “High-Temperature phase relations in the system Y 2O 3-Y 2O 3.WO 3,”J. Am. Ceram. Soc. 63, 644–647.Google Scholar
Louër, D. (1991). “Indexing of powder diffraction patterns,” Mater. Sci. Forum 79–82, 17–26.Google Scholar
Loüer, D., and Langford, J. I. (1988). “Peak shape and resolution in conventional diffractometry with monochromatic X-rays,” J. Appl. Crystallogr. 21, 430–437.Google Scholar
Louër, D., and Louër, M. (1972). “Méthode d’essais et d’erreurs pour l’indexation automatique des diagrammes de poudre,” J. Appl. Crystallogr. 5, 271–275.CrossRefGoogle Scholar
McCarthy, G. J., and Fisher, R. D. (1971). “Synthesis and X-ray study of fluorite related phases in the system Ho 2O 3-WO 3,”Mater. Res. Bull. 6, 591–602.Google Scholar
McCarthy, G. J., Fisher, R. D., Johnson, Jr., G. G., and Gooden, C. E. (1972). “Crystal chemistry and compound formation in the systems rare earth sesquioxide-WO 3,” National Bureau Stand. Special Publication No. 364, Solid State Chem., Proceedings of Fifth Material Research Symposium, 397–411.Google Scholar
Mighell, A. D., Hubbard, C. R., and Stalick, J. K. (1981). NBS*AIDS80: A FORTRAN Program for Crystallographic Data, US Natl. Bur. Stand. Tech. Note No 1141, p. 54 (NBS*AID83 is an expanded version of NBS*AIDS80).Google Scholar
Ray, S. P., and Cox, D. E. (1975). “Neutron diffraction determination of the crystal structure of Ce 7O 12,”J. Solid State Chem. 15, 333–343.CrossRefGoogle Scholar
Rodriguez-Carvajal, J. (1990). “FULLPROF: A program for Rietveld refinement and pattern matching analysis,” Collected Abstracts of Powder Diffraction Meeting (Toulouse, France), p. 127.Google Scholar
Shannon, R. D. (1976). “Revised effective ionic radii and systematic studies of interatomic distances in halides and chalcogenides,” Acta Crystallogr., Sect. A: Cryst. Phys., Diffr., Theor. Gen. Crystallogr. A32, 751–767.CrossRefGoogle Scholar
Smith, G. S., and Snyder, R. L. (1979). “F(N): A criterion for rating powder diffraction patterns and evaluating the reliability of powder pattern indexing,” J. Appl. Crystallogr. 1, 108–113.Google Scholar
Trunov, V. K., and Kudin, O. V. (1977). “Rare-earth element oxide tungstates,” Russ. J. Inorg. Chem. 22, 646–647.Google Scholar
Trunov, V. K., Tuushevskaya, G. I., and Afonskii, N. S. (1968). “Investigation of the double oxides formed in the reaction of Nd 2O 3, Sm 2O 3 and Er 2O 3 with tungsten (VI) oxide,” Russ. J. Inorg. Chem. 13, 491–493.Google Scholar
Von Dreele, R. B., Eyring, L., Bowman, L. N., and Yarnell, J. L. (1975). “Refinement of the crystal structure of Pr 7O 12 by powder neutron diffraction,” Acta Crystallogr., Sect. B: Struct. Crystallogr. Cryst. Chem. B31, 971–974.Google Scholar
Wells, A. F. (1984). Structural Inorganic Chemistry, 5th ed. (Oxford Science, Oxford).Google Scholar
Zalkin, A., Templeton, D. H., and Karraker, D. G. (1969). “The crystal and molecular structure of the heptacoordinate complex tris(diphenylpropanedionato)aquoholmium, Ho(C 6H 5COCHCOC 6H 5)3.H 2O,”Inorg. Chem. 8, 2680–2684.CrossRefGoogle Scholar