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Li3SbS3 was synthesized by solid-state reaction of stoichiometric amounts of Li2S and Sb2S3 in the ratio 3:1. The product is air and moisture sensitive. The crystal structure was determined from single crystals at room temperature. Pale grey Li3SbS3 crystallizes in the orthorhombic space group Pna21 (no. 33) with a = 7.9671(5) A, b = 6.7883(5) A, c = 10.0912(8) A, V = 545.76(7) A3, and Z = 4 (data at 20 °C). Antimony and sulfur atoms build isolated, trigonal pyramidal [SbS3]3– units, which are stacked along [100]. These [SbS3]3– units are connected by [LiSx]-polyhedra. The lithium ions have either a distorted tetrahedral coordination by sulfur in the case of Li2 and Li3 or a distorted square pyramidal environment in the case of Li1. The crystal structure is isotypic with Li3AsS3, which was obtained by reaction of stoichiometric amounts of lithium, arsenic, and sulfur in the ratio 3:1:3 in an excess of LiI. LiI serves only as a flux and is not incorporated in the crystal structure. Li3AsS3 crystallizes as colorless rods, space group Pna21 (no. 33) with a = 8.090(1) A, b = 6.658(1) A, c = 9.868(1) A, V = 531.5(1) A3, and Z = 4 (data at 20 °C). Both compounds are confirmed as semiconductors with bandgaps close to 3 eV from DFT-calculations with GGA and hybrid functionals. Impedance spectroscopic measurements of Li3SbS3 show a specific conductivity of σ = 1.6 × 10–9 Ω–1 cm–1 at 323 K and of σ = 5.4 × 10–5 Ω–1 cm–1 at 573 K. The activation energy is EA = 0.72 eV. Raman spectra of Li3SbS3 are dominated by the stretching modes of the [SbS3]3– units at 333, 317, and 301 cm–1 at room temperature.

Crystals of the Lewis-acid-base adduct MeInCi 2 · H 2 N t Bu (I) are formed, when dimethylbis(t-butylamino)silane is allowed to hydrolyze in the presence of methylindium dichloride. I crystallizes in the orthorhombic, acentric space group P 2 1 2 1 2 1 with cell dimensions a 1544.6(3), b 1071.4(2), c 628.6(1) pm and Z = 4. The X-ray structure determination ( R = 0.041) reveals I to be a polymer in the solid state, the molecules being held together by NH ⋯ Cl interactions, forming an one-dimensional chain structure. The indium atom has a four-fold, tetrahedral coordination. Remarkable intramolecular distances are: N-In 221 pm (very short), In-C(1) 214 pm and NC(2) 154 pm (both elongated) and In-Cl 240 pm. The Lewis acidity of the indium atom in I is compared with that of the tin atom in Me 2 Si(N t Bu) 2 Sn · H 2 N t Bu (II) and found to be much higher on the basis of the structural data.

The Crystal Structure of a Bridged 1,2,3-Oxadiazolidin-5-one Derivative 3-(2-Allylphenyl)-4-phenylsydnone (1) undergoes in solution an intramolecular, 1,3-dipolar cycloaddition reaction to give 2-oxo-1-phenyl-1,5-methano-1,2,4,5,6,11-hexahydro[1,2,3]oxadiazolo[3,2-a]cinnoline (2). The unique 1,2,3-oxadiazolidin-5-one structure of this molecule has been proved by X-ray analysis. The crystal structure has been solved by direct methods and refined by full-matrix least squares calculations to R = 0,046. The crystal system is orthorhombic, space group Pbca, with unit cell dimensions a = 10,546,b = 15,482, c = 16,531A.