2016/05/01 by Sebastian Bette, Christine Rincke, Robert E. Dinnebier +1 · 1 citation
Environmental Science · Chemistry · Materials Science · #Chemical Synthesis and Characterization #Radioactive element chemistry and processing #X-ray Diffraction in Crystallography
paper · doi:10.1002/zaac.201600044
Abstract A sample of pure, artificial hellyerite was synthesized in aqueous solution at 0 °C. The recorded X‐ray diffraction pattern completely agrees with the reference data given for natural hellyerite. Laboratory high resolution X‐ray powder diffraction, applying global optimization methods and Rietveld refinement, was employed to solve the crystal structure. Synthetic hellyerite was determined to crystallize in the primitive monoclinic space group P 2/ m (no. 10) with a = 10.769(2) Å, b = 7.295(2) Å, c = 9.343(2) Å, and β = 94.042(2)°. The crystal structure consists of edge‐linked, isolated pairs of Ni 2 (CO 3 ) 2 (H 2 O) 8 octahedra and non‐coordinating water molecules. According to structure solution and thermal analysis the molecular formula of hellyerite was corrected from NiCO 3 · 6H 2 O to NiCO 3 · 5.5H 2 O. The title compound was characterized by scanning electron microscopy, IR‐, Raman‐, and UV/Vis spectroscopy.