April 1996 issue
The Al atoms in Na9[Al(OH)6]2(OH)3.6H2O have octahedral coordination geometry and exist as monomeric [Al(OH)6]3− anions. The Na+ ions also have octahedral coordination geometry and are coordinated by OH− ions and water molecules. The NaO6 octahedra are linked through common edges, incorporating the [Al(OH)6]3− octahedra, to yield a three-dimensional network.
The orthophosphate Cs8Fe15F10(PO4)12 is built from layers of vertex-sharing Fe polyhedra linked into a framework by PO4 tetrahedra. The Fe3+ ions have octahedral coordination geometry and the Fe2+ ions have octahedral, tetrahedral and distorted tetragonal pyramidal coordination environments.
The three-dimensional polymeric complexes [Bi(SCN)6La(H2O)3].2H2O and [Bi(SCN)6Nd(H2O)3].2H2O are isomorphic with and have a similar structure to the LaFe(CN)6.5H2O structure type. The bond lengths in the coordination polyhedra and the hydrogen bonding in the structures are discussed.
The structure of Co2Si(P2O7)2 contains SiO4 tetrahedra, eclipsed P2O7 groups [with a P-O-P angle of 132.3(1)°] and compressed CoO6 octahedra. The CoO6 octahedra share edges to form Co2O10 units, which are linked via four vertices to form a two-dimensional network.