The structures of LiY9(SiO4)6O2 and NaY9(SiO4)6O2 have been determined from single-crystal X-ray diffraction data collected near room temperature and at 100 K. The structures are very similar to one another and to that of fluorine apatite.
The title compound crystallizes with a partially ordered Pu3Pd5-type structure in space group Cmcm. The 8f and 4c positions are statistically occupied by Ga and Sn atoms, while the 8g position is occupied overwhelmingly by Sn atoms.
The crystal structure of a barium titanate that had been reported previously in the centrosymmetric space group C2/m was found to be non-centrosymmetric, with space group C2. The present results are in accordance with the recently observed ferroelectricity of this compound.
LaInO3, a promising ion conductor for a holistic solid oxide fuel cell, was synthesized by a solid-state reaction method. The structure was refined by the Rietveld method using X-ray powder diffraction data. The structure of LaInO3 is distorted by the in-phase and antiphase tilting of oxygen octahedra in the a+b−b− system of the InO6 polyhedra.
The crystal structures of the two bismuth(III) oxalate hydrates [Bi2(C2O4)3(H2O)4]·4H2O and [Bi2(C2O4)3(H2O)4]·2H2O are both based on three-dimensional networks of nine-coordinated Bi atoms, connected by tetradentate oxalate groups. The ligand and `free' water molecules are located in channels and voids.