Ilmenite-type Na(FeTe)O.

Na(FeTe)O ( = 3) or Na(FeTe)O ( = 2), tris-odium iron(III) ditellurium(VI) nona-oxide, adopts the ilmenite (FeTiO, = 6) structure type with the Ti site (site symmetry 3.) replaced by Na and the Fe site (site symmetry 3.) replaced by a mixed-occupied (Fe,Te) site in a Fe:Te ratio of 1:2.

Synthesis and crystal structure of (NH)[Ni(HAsO)(AsO)(OH)].

The title compound, ammonium trinickel(II) hydrogen arsenate arsenate di-hydroxide, was synthesized under hydro-thermal conditions. Its crystal structure is isotypic with that of K[Cu(HAsO)(AsO)(OH)] and is characterized by pseudo-hexa-gonal (001) [NiAsO(OH)O(OH)] layers formed from vertex- and edge-sharing [NiO(OH)] octa-hedra and [AsO(OH)] tetra-hedra as the building units. The hydrogen atom of the OH group shows occupational disorder and was refined with a site occupation factor of 1/2, indicating the equal presence of [HAsO] and [AsO] groups.

Cadmium phosphates Cd(PO)OH and Cd(PO)(OH) crystallizing in mineral structures.

Single crystals of two basic cadmium phosphates, dicadmium orthophosphate hydroxide, Cd(PO)OH, and penta-cadmium bis-(orthophosphate) tetra-kis-(hydroxide), Cd(PO)(OH), were obtained under hydro-thermal conditions. Cd(PO)OH adopts the triplite [(Mn,Fe)(PO)F] structure type. Its asymmetric unit comprises two Cd, one P and five O sites, all situated at the general Wyckoff position 8 of space group 2/; two of the O atoms are positionally disordered over two sites, and the H atom could not be localized.

Crystal structure of K[Zn(CO)].

The crystal structure of K[Zn(CO)], hexa-potassium tetra-carbonato-zincate(II), comprises four unique potassium cations (two located on a general position, and two on the twofold rotation axis of the space group 2/) and a [Zn(CO)] anion. The Zn atom of the latter is located on the twofold rotation axis and is surrounded in a slightly distorted tetra-hedral manner by two pairs of monodentately binding carbonate groups, with Zn-O distances of 1.9554 (18) and 1.