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ChemInform Abstract have been prepared by reaction of the elements in a tin flux (850-920 rc C, 1-2 weeks). The compounds R5Co19P12 (R: Y, Gd-Lu) crystallize in the Sc5Co19P12-type structure (hexagonal, space group P6m), which is refined for Ho5Co19P12. The new compounds GdCo3P2 (I), ErCo5P3 (II), and TmCo5P3 (III) crystallize with the closely related HoCo3P2-type ((I)) and YCo5P3-type ((II) and (III)) structures, respectively.

U2Mo30P19 (VIII) are prepared from mixtures of the elements in most cases with elemental Sn as a flux (alumina crucibles, 650-950 C, 7-10 d). The phosphides are characterized by powder and single crystal XRD. Compounds (I), (II), and (III) crystallize with the YCo 5 P 3 -type structure in the orthorhombic space group Pnma (Z = 4 for (II)). (IV-VI) crystallize with the -UCr 6 P 4 (LiCo 6 P 4 ) structure type in the hexagonal space group P6m2 (Z = 1 for (IV)). Compound (VII) crystallizes in the hexagonal space group P6 with the Zr 2 Fe 12 P 7 -type structure. (VIII) crystallizes in the hexagonal space group P6 with the U 2 Cr 30 P 19 (Zr 2 Cr 30 P 19 ) structure type. The crystal structures of these compounds with a metal to phosphorus ratio close to 2:1 are briefly discussed. -(JEITSCHKO*, W.; ALBERING, J. H.; BRINK, R.; JAKUBOWSKI-RIPKE, U.; REINBOLD, E. J.; Z. Anorg. Allg. Chem. 640 (2014) 12-13, 2449-2457 (NH 3 stream, 760 C, 1 h; 43% yield). As a representative of the anatase structure (aristotype) -TaON crystallizes in the tetragonal space group I4 1 /amd (Z = 4, powder XRD). An irreversible phase transformation to baddeleyite-type -TaON is observed between 800 and 850 C. While quantum-chemical calculations confirm the metastable character of -TaON, its transformation to -TaON is kinetically controlled. The anion distribution of the anatase-type phase is theoretically studied. Configurations with maximum N-N distances are shown to be most stable. The calculated band edge energies indicate that -TaON is a promising photocatalyst for redox reactions, e.g. water splitting. -Crystals of the title compound are prepared by condensation of NH 3 onto a mixture of Na 2 Cs 2 Ge 9 (obtained from the elements at 743.15 K for 72 h) and dibenzo-18-crown-6, followed by storage of the reaction mixture for one year at 235.15 K. The compound crystallizes in the monoclinic space group P2 1 /m with Z = 8. The coordination environments of the Cs cations contain three to four clusters, coordinating via their corners, edges, or triangular faces, and additionally three to six ammonia molecules. The first coordination sphere of cationic sites, which are fully occupied by Na is built by five ammonia molecules in a distorted trigonal bipyramidal manner. There are also mixed Na/Cs cation sites in which four ammonia molecules coordinate to Cs, whereas in the case of Na, one additional ammonia molecule is present. -(GAERTNER, S.; SUCHENTRUNK, C.; KORBER*, N.; Acta Crystallogr., Sect. C: Cryst. Struct. Commun. 70 (2014) (x = 0, 0.1, 0.23, 0.4) nanoflowers are prepared by hydrothermal treatment of LuCl 3 , BiCl 3 , and Te with NaBH 4 as reductant and EDTA as complexing agent (autoclave, 433 K, 24 h). The obtained nanopowders are pelletized by hot pressing, and the thermoelectric properties are investigated in relation to the Lu levels. The results show that Lu doping reduces the electrical resistivity largely, while it does not affect the Seebeck coefficient very much and therefore, results in a high power factor. Because th...

The title compounds crystallize with a new hexagonal structure type, which was determined from single‐crystal diffractometer data of Gd4Co13(Si, P)9: space group P$\bar{6}$m2, a = 1041.9(4) pm, c = 372.7(1) pm, Pearson symbol hP26. The structure was refined to a residual of R = 0.033 for 18 variable parameters and 190 structure factors. The silicon and phosphorus atoms (X) are located at three crystallographic positions with eight or nine metal neighbors forming capped trigonal prisms most likely with random occupancy. The gadolinium atoms occupy two sites, each with 6 X neighbors forming trigonal prisms. This coordination is augmented by 14 metal atoms (mostly cobalt atoms), thus increasing the coordination numbers of both gadolinium positions to 20. The four different cobalt atoms have 3, 4, or 5 X neighbors with 6 or 8 additional metal neighbors. The relative strengths of the chemical bonds correlate very well with the coordination numbers. The structure belongs to a large structural family with a metal to metalloid ratio of approximately 2:1, where all atoms are situated on two alternating mirror planes and most of the metalloid atoms (M, mainly silicon, phosphorus, and their homologues) with the coordination number 9 are situated in tricapped prisms of the metal atoms (R = large electropositive metals, mainly rare earth elements and actinoids; T = transition metals). It can be classified as the third member (n = 3) of a topological series R$_{(n-1)^2}$Tn(n+2)–2M$_{n^2}$, where the structures of WC and α‐UCr6P4 (LiCo6P4) are the members with n = 1 and n = 2, respectively.

The new ternary phosphides ScFe5P3 (I), Sc(Ta0.18Fe0.82)Fe4P3 (II), ZrFe5P3 (III), ScRu6P4 (IV), ErRu6P4 (V), ZrCr6P4 (VI), Nd2Ru12P7 (VII), and U2Mo30P19 (VIII) are prepared from mixtures of the elements in most cases with elemental Sn as a flux (alumina crucibles, 650—950 °C, 7—10 d).