Gorceixite from Catalão, Goiás, Brazil: rietveld crystal structure refinement
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چکیده
منابع مشابه
Crystal structure of Na2HfSi2O7 by Rietveld refinement
The structure of triclinic disodium hafnium disilicate, Na2HfSi2O7, has been determined by laboratory powder X-ray diffraction and refined by the Rietveld refinement. The structure is a framework made of alternate layers of HfO6 octa-hedra and SiO4 tetra-hedra linked by common O atoms. Sodium atoms are located in the voids of the framework, aligned into tunnels along the [010] direction. Na2HfS...
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Mackinawite,tetragonal FeS, has been synthesised by reacting iron with Na2S solutions. A Rietveld structure refinement of X-ray powder diffractipn data, recorded using X-rays monochromated from synchrotron radiationwith a wavelength of 0.6023 A, has been performed. The structure has been refined in the tetragonal sJ'.!lcegroup, P4/nmm, and has the following cell parameters: a = 3.6735(4), c = 5...
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ReO2 presents two crystalline variants, with monoclinic and orthorhombic structures. The former is metastable and irreversibly transforms to an orthorhombic structure above 460oC. The structure of the latter was determined from studies on monocrystalline samples, whereas for the monoclinic variant there are no single crystals available so far. It was found only one monoclinic variant and the st...
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ژورنال
عنوان ژورنال: Geologia USP. Série Científica
سال: 2007
ISSN: 1519-874X
DOI: 10.5327/z1519-874x2007000200002