
%0 Journal Article
%A Hoskins, BF 
%A Linden, A 
%T The Nature of the Hexahydrates of Divalent Transition Metal Cations: The Structures of the Hexafluorogermanate Hexahydrates of Iron(II), Cobalt(II) and Nickel(II)
%J Australian Journal of Chemistry
%D 1987/03/01
%V 40
%N 3
%P 565-577
%K 
%R https://doi.org/10.1071/CH9870565
%U https://www.publish.csiro.au/paper/CH9870565 
%X The crystal and molecular structures of the room temperature phases of MII(H2O)6GeF6 (M = Fe, Co, Ni) are reported. In each structure the M(H2O62+ and GeF62- octahedra are in approximate CsCl -type packing with hydrogen bonding between the ions. Differences in the structures arise from disorder in the orientations of the octahedra . Fe(H2O)6GeF6 crystallizes in the spate group R3M, with three molecules in the unit cell of dimensions ahex , 9.728(2), Chex 9.796(2) Å. Refinement converged with R 0.0135 and Rw 0.0137, 286 independent observed reflections being used. There is disorder of both fluorine and oxygen atoms between two positions related by a mirror plane, which raises the 3 symmetry within each octahedron to overall 3m symmetry. Ni(H2O)6GeF6 crystallizes in the spate group R3 with three molecules in the unit cell of dimensions ahex 9.443(1), chex 9 .77O(l) Å. Refinement converged with R 0.016 and R, 0.018 for 444 independent observed reflections. There is disorder only of the fluorine atoms between two positions unrelated by any symmetry element. CO(H2O)6GeF6 crystallizes in the space group P21/c with two molecules in the unit cell of dimensions a 6.552(2), b 9.577(2), c 8.520(1) Å, ,&#946; 99.74(2)º. Refinement converged with R 0.042 and R, 0.054 for 1232 independent observed reflections. The structure is not disordered and deviates only slightly from rhombohedral symmetry. 
