Hostname: page-component-586b7cd67f-dsjbd Total loading time: 0 Render date: 2024-11-26T12:27:48.483Z Has data issue: false hasContentIssue false

On the space group of garronite

Published online by Cambridge University Press:  10 January 2013

Gilberto Artioli
Affiliation:
Dipartimento di Scienze della Terra, Università di Milano, via Botticelli 23, I 20133 Milano, Italy
Maurizio Marchi
Affiliation:
Dipartimento di Scienze della Terra, Università di Milano, via Botticelli 23, I 20133 Milano, Italy

Abstract

The crystal structure of the natural zeolite garronite from Goble, Oregon has been refined using high resolution synchrotron X-ray powder diffraction data. Garronite has the same tetrahedral aluminosilicate framework as gismondine [GIS], and earlier structural models indicated a strong tetragonal pseudosymmetry. Proposed models in the literature were based on the Im2 and I41/a space groups, on account of symmetry lowering from the topological I41/amd space due to partial cation/water molecule order in the zeolitic cavities. Test structure analysis has been performed in all possible space subgroups including monoclinic space groups, and the refinement has been successfully carried out in space group I2/a (C2/c). The resulting monoclinic structure model is to be preferred over the tetragonal ones on the basis of: (1) lower agreement indices of the refinement; (2) a chemically sound framework geometry; and (3) a more satisfactory interpretation of the Ca atoms coordination in the extraframework cages.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1999

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

Albert, B. R., Cheetham, A. K., Stuart, J. A., and Adams, C. J. (1998). “Investigations on P zeolites: synthesis, characterization, and structure of highly-crystalline low-silica NaP,” Microporous and Mesoporous Materials 21, 133142.CrossRefGoogle Scholar
Artioli, G. (1992). “The crystal structure of garronite,” Am. Mineral. 77, 189196.Google Scholar
Chiari, G., and Ferraris, G. (1982). “The water molecule in crystalline hydrates studied by neutron diffraction,” Acta Crystallogr., Sect. B: Struct. Crystallogr. Cryst. Chem. 38, 23312341.CrossRefGoogle Scholar
Coombs, D. S. (1998). “Recommended nomenclature for zeolite minerals,” Report of the Subcommittee on Zeolites of the International Mineralogical Association, Commission on New Minerals and Mineral Names.CrossRefGoogle Scholar
Gottardi, G., and Alberti, A. (1974). “Domain structure in garronite: A hypothesis,” Miner. Mag. 39, 898899.CrossRefGoogle Scholar
Gottardi, G., and Galli, E. (1985). Natural Zeolites, (Springer-Verlag, Berlin).CrossRefGoogle Scholar
Howard, D. G. (1994). “Crystal habit and twinning of garronite from Fara Vicentina, Vicenza (Italy),” N. J. Mineral. Mh. 2, 9196.Google Scholar
Larson, A. C., and Von Dreele, R. B. (1998). GSAS, General Structure Analysis System. Los Alamos National Laboratory, document LAUR 86-748.Google Scholar
Meier, W. M., Olson, D. H., and Baerlocher, C. (1996). Atlas of Zeolite Structure Types. 4th Ed. (Butterworths, Guildford, England).Google Scholar
Norby, P. (1997). “Synchrotron powder diffraction using imaging plates: Crystal structure determination and Rietveld refinement,” J. Appl. Crystallogr. 30, 2130.CrossRefGoogle Scholar
Schröpfer, L., and Joswig, W. (1997). “Structure analyses of a partially dehydrated synthetic Ca-garronite single crystal under different T, p H2O conditions,” Eur. J. Mineral. 9, 5366.CrossRefGoogle Scholar
Tschernich, R. W. (1992). Zeolites of the World (Geoscience Press, Phoenix, AZ).Google Scholar