The crystal structure of ammonium hexaaquanickel(II) phosphate [Ni(H

Crystal Structure, Phenyltrimethylammonium-dekabromotriplumbate [PhMe3N]4[Pb3Brio] crystallizes with monoclinic symmetry in the space group P 2 i/c with lattice parameters of a -1295.5, b -951.5, c = 2294.7 pm, ß = 110.24° and Z = 2. The unit cell contains eight cations and two [Pb3Br|0]4~ anions, each of which shares four vertices with neighbouring anions resulting in a twodimensional type.

structure structure (solids and liquids) D 2000 -013Crystal Structure of [PhMe 3 N] 4 [Pb 3 Br 10 ].-The title compound (III) crystallizes in the monoclinic space group P2 1 /c with Z = 2 (single crystal XRD). The structure consists of a two-dimensional anionic partial structure of Cs 4 Mg 3 F 10 type formed by sharing of four corners of each [Pb 3 Br 8 Br 4/2 ] 4− anion, which in turn consists of three face-sharing PbBr 6 octahedra.-(WIEST, TH.; BLACHNIK, R.; REUTER, H.

Source of materialPbBr 2 and [Ph 3 P-CH=CH-PPh 3 ][Br 2 ] were both dissolved in aqueous HBr, the solutions were mixed and water was slowly evaporated. After several hours a fine crystalline yellow powder precipitated. For the preparation of single crystals 1.5 g of this product and 5 ml H2O were filled into a glass ampoule which was sealed and heated to 45 3 K. The ampoule was cooled with a rate of 10 K/min to ambient temperature. DiscussionLead atom is coordinated by four bromide ligands, in form of a trigonal ψ-bipyramide with one equatorial position occupied by the s 2 -pair. The axial Pb-Br bond lengths are 2.99 Ä, the equatorial lengths 2.70 Ä, Br(ax)-Pb-Br(eq) angles are in the range 95.53° to 99.42°, the bond angle between the two axial Br-atoms is 159.0°. The data agree with those observed in comparable bromoplumbates(II) [1]. The distorted ψ-bipyramide was so far not observed in the structure of lead bromides with organic cations. Cations and anions form waved layers, which are stacked along the α-axis in the order A,A,A. Bond distances and bond angles in the cation agree well with the data of Stang and Zhdankin [2], The compound was investigated with a differential scanning calorimeter. Between 153 Κ and 423 Κ no phase transition was detected.

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