Abstract. The compounds Li 8 EN 2 with E = Se, Te were obtained in form of orange microcrystalline powders from reactions of Li 2 E with Li 3 N. Single crystal growth of Li 8 SeN 2 additionally succeeded from excess lithium. The crystal structures were refined using single-crystal X-ray diffraction as well as X-ray and neutron powder diffraction data (I4 1 md, No. 109, Z = 4, Se: a = 7.048(1) Å, c = 9.995(1) Å, Te: a = 7.217(1) Å, c = 10.284(1) Å). Both compounds crystallize as isotypes with an anionic substructure motif known from cubic Laves phases and lithium distributed over four crystallographic sites in the void space of the anionic framework. Neutron powder diffraction pattern recorded in the temperature range from 3 K to 300 K and X-ray diffraction patterns using synchrotron radiation taken from 300 K to 1000 K reveal the structural stability of both compounds in the studied temperature range until decomposition. Motional processes of lithium atoms in the title

The ternary nitridochromate Ce 2 [CrN 3 ] (orthorhombic Immm, a = 378.56(1) pm, b = 340.88(2) pm, c = 1251.27(4) pm) was synthesized in single phase form from the binary nitrides utilizing the decomposition of CrN to Cr 2 N. Magnetic susceptibility measurements * Prof. Dr. R. Niewa

A redetermination of the structure of`La 32.66 Fe 11 S 60 ' in the trigonal space group R3m led to the new formula La 52 Fe 12 S 90 and to a rede®nition of the structure type. In the structure, the Fe 2+ cations occur in Fe 2 S 9 dimers of face-sharing octahedra (with 3m symmetry). The dimers are linked by face-and vertex-sharing bi-and tricapped LaS 6 trigonal prisms (with m symmetry) to form a three-dimensional network containing two types of cuboctahedral cavities. The larger cavities remain empty, while the smaller ones accommodate alternative sites for disordered La 3+ cations. CommentIn a search for materials with interesting magnetic properties, we have begun a reinvestigation of the R±Fe±S system (R = rare earth metal). With the larger rare-earth metals, phases of three different compositions are formed, viz. R 2 Fe 2À S 5 (R = La, Ce and Pr), R 3 Fe 2À S 7 (R = La, Ce, Pr and Nd) and R 52 Fe 12 S 90 (R = La, Ce, Pr and Nd) (Collin et al.

The cubic Perovskite (Ca2EuN0.75)Sn was synthesized in a solid state reaction from EuN, Ca, and Sn. Nitrogen deficiency and Ca/Eu disorder is in agreement with results from chemical analysis, X‐ray diffraction, and Mössbauer spectroscopy. Magnetic susceptibility measurements as well as Mössbauer and X‐ray absorption spectroscopy indicate a mixed‐valent situation with di‐ and trivalent europium, apparently situated together with calcium on one crystallographic site. According to electrical resistivity measurements the title compound represents a heavily doped semiconductor.

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