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The structure of Ga2S2Te (M r = 331.16) has been determined from single-crystal X-ray data. The cell is tetragonal, a = 7.09 (4), c :--: 10.21 (5) A, Z = 4, space group I4tmd, V = 1918 /ka, --xD29aK = 4.03 (8), D c = 4.08 Mg m -a. The structure was refined to a final R of 0.018. The Ga atoms are in fourfold, the Te atoms in twofold and the S atoms in threefold coordination. This structure is essentially built up of GaS3Te tetrahedra, which share their four apices in a three-dimensional arrangement. These tetrahedra are linked in chains which form layers parallel to the (001) plane. In two contiguous layers, the chains are successively parallel to the a and b axes.

The powder data for pipemidic acid trihydrate are reported. This compound is triclinic with a=8.570 (3), b= 8.514 (3), c = 15.208 (6) A, ~ = 105.14 (4),/3= 110.84 (5), ~ = 113.96 (5) °. Z

The powder data for [2.1.2.1]paracyclophan is reported. This compound is monoclinic with a = 21.44 (4), b = 17.22 (6), c = 9.70 (4) Å, γ = 141.30 (3)°, Z = 4.

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