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EuZrSe3, Mr = 480.07, orthorhombic, Pnma, a = 8.849 (2), b = 3.937 (1), c = 14.348 (5) •, V = 499.9 (2) ,~3, Z = 4, Dx = 6.38 g cm- 3, a(Mo Kay) = 0.7093 ,~, /1, = 359.6 cm-1, F(000) = 805 (including anomalous dispersion), T = 294 K, R(F 2) = 0.096 for 973 averaged reflections (including those having Fo2 3o-(Fo2). The structure of EuZrSe3 consists of columns of double edge-sharing Zr octahedra. These columns are linked together by Eu bicapped trigonal prisms. Introduction. The phase Ln2MQ5 (Ln = rare earth; M = Zr, Hf; Q = S, Se) exists for most rare earths with the exception of Eu (Cherkasova & Serebrennikov, 1977; Donohue & Jeitschko, 1974; Jeitschko & Donohue, 1975; Kokhno & Serebrennikov, 1977). By virtue of the high stability of its divalent state, Eu * To whom correspondence should be addressed. 0108-2701/92/050771-03506.00 forms the phases EuZrS3 and EuHfS3, which adopt a distorted perovskite structure of the GdFeO3 type (Kazarbina, Maksimov & Serebrennikov, 1981; Lelieveld & IJdo, 1980; Serebrennikov, Senova & Cherkasova, 1979). As part of a general program to elucidate new ternary chalcogenides, we report here the structure of a new ternary selenide, EuZrSe3. EuZrSe3 belongs to the NH4CdC13 structure type (Muller & Roy, 1974), a class of compounds

The new oxychloride InTeO(3)Cl was synthesized from a mixture of In(2)O(3), InCl(3) and TeO(2). Its structure has been determined from single-crystal X-ray diffraction data. The structure is composed of layers separated by a van der Waals gap. The layers consist of edge-sharing chains of [InO(4)Cl(2)] octahedra linked through [TeO(3)] trigonal pyramids. No free Cl atoms are located between the layers.

Titanates occupy an important place among advanced oxide materials. After characterization of MLi2Ti6O14 compounds in the ternary oxide systems MO Li2O TiO2 (M = Sr, Ba, Pb) [1],[2], two new titanates of Sr, Li and a 3d transitionmetal, SrLiMTi4O11 (where M = Cr, Fe) were discovered. Single crystals were obtained by spontaneous nucleation using LiBO2 as flux. The SrLiCrTi4O11 structure was refined using 1491 independent reflections in orthorhombic space group Pmna, with a=13.818A, b=5.755A, c=9.901A, Z=4, R1=0.021 and wR2=0.058. The SrLiFeTi4O11 structure was refined using 5005 independent reflections in orthorhombic space group Pbcn, with a=13.878A, b=11.496A, c=19.895A, Z=16, R1=0.036 and wR2=0.105. Structures can be described by the close-packed arrangement of strontiumand oxygen atoms. The unit cell contains 6 ’’compact planes’’ perpendicular to [100] in the layer sequence ABACBC ((chc)2). Titanium, chromium or iron atoms occupy some of the created interstitial octahedral sites whereas lithium atoms are situated in tetrahedral sites. Depending on the synthesis conditions of SrLiCrTi4O11, the chromium and titanium atom distributions over the four allowed crystallographic sites are not the same. Having a similar compact-planes sequence, SrLiCrTi4O11 and SrLiFeTi4O11 structures differ in the arrangement of strontium and oxygen atoms per layer of close packing which also induces correlated variation in the Li-tetrahedra distribution.