The structures of the natural zeolite garronite, NaCa2.5Al6Si10O32.13H2O, from Goble, Oregon, and Fara Vicentina, Italy, have been determined and refined by X-ray powder diffraction methods with the use of the full-profile Rietveld technique. The framework topology has the gismondine structure type (GIS), although the topological symmetry I4(1)/amd is lowered to I4BARm2. Cell dimensions are Goble, a = 9.9266(2), c = 10.3031(3) angstrom; Fara Vicentina, a = 9.8712(2), c = 10.2987(3) angstrom. The space group assumed in the refinements accounts for the presence in the garronite powder pattern of reflections violating the d glide extinctions. Deviation from the maximum framework symmetry can be explained in terms of cation and H2O arrangements in the zeolitic cavities.
The crystal structure of garronite
ARTIOLI, GILBERTO
1992
Abstract
The structures of the natural zeolite garronite, NaCa2.5Al6Si10O32.13H2O, from Goble, Oregon, and Fara Vicentina, Italy, have been determined and refined by X-ray powder diffraction methods with the use of the full-profile Rietveld technique. The framework topology has the gismondine structure type (GIS), although the topological symmetry I4(1)/amd is lowered to I4BARm2. Cell dimensions are Goble, a = 9.9266(2), c = 10.3031(3) angstrom; Fara Vicentina, a = 9.8712(2), c = 10.2987(3) angstrom. The space group assumed in the refinements accounts for the presence in the garronite powder pattern of reflections violating the d glide extinctions. Deviation from the maximum framework symmetry can be explained in terms of cation and H2O arrangements in the zeolitic cavities.Pubblicazioni consigliate
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