Structure of BaGaF5•2H2O from Conventional and Synchrotron Powder Diffraction Data
نویسنده
چکیده
The compound BaGaF5•2H2O was prepared at moderate temperature, 60-80°C, from HF aqueous solution. It crystallizes in the monoclinic system, space group P21/m with a = 10.0626(6) Å, b = 5.8070(1) Å, c = 4.9788(3) Å, β = 103.359(7)° and Z = 2. The structure was determined from conventional powder diffraction data by direct methods and refined from synchrotron data to RP = 10.8 and RB = 4.0 % by the Rietveld method using a program modified to account for anisotropic line broadening. The bidimensional structure is built up from layers of isolated [GaF5(H2O)] octahedra interconnected by [BaF11(H2O)] cuboctahedra.
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