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The five new thioantimonates(III) ( i prH) 2 [Sb 8 S 13 ] ( I ), (1,2-dapH) 2 [Sb 8 S 13 ] ( II ), (1,3-dapH 2 )[Sb 8 S 13 ] ( III ), (dienH 2 )[Sb 8 S 13 ]⋅1.5H 2 O ( IV ), and (C 6 H 9 N 2 )[Sb 8 S 13 ]⋅2.5H 2 O ( V ) were synthesised under solvothermal conditions ( i pr = iso-propylamine; 1,2-dap = 1,2-diaminopropane; 1,3-dap = 1,3-diaminopropane; dien = diethylentriamine; C 6 H 9 N 2 = 3-(aminoethyl)-pyridine). The structures of compounds I and II are topological very similar and a central motif is a Sb 10 S 10 ring. On both sides of this ring Sb 5 S 5 rings are condensed. These rings are connected via Sb 4 S 4 rings leading to the sequence Sb 10 S 10 –Sb 5 S 5 –Sb 4 S 4 –Sb 5 S 5 –Sb 10 Sb 10 in the [010] direction. Further interconnection into the two-dimensional [Sb 8 S 13 ] 2− anion produces a large central Sb 18 S 18 ring with dimensions of 11⋅11 A 11 ⋅ 11 A in both compounds. The two atoms thick layers are linear and stacked along the a axis generating large channels running along [010]. The layered anion of compound III is constructed by interconnection of the SbS 3 and SbS 4 units yielding Sb 19 S 19 , Sb 14 S 14 , Sb 13 S 13 , and Sb 8 S 8 rings. The linear layers are two atoms thick and are stacked perpendicular to [001] to form channels running along the same direction. The last two compounds IV and V show a similar network topology. The layered anion is constructed by SbS 3 trigonal pyramids and SbS 4 units. The layer contains a Sb 12 S 12 rings as the main structural motif. The corrugated layers extending in the (100) plane are two atoms thick and are stacked in a manner that large tunnels run along [100]. The total potential solvent areas are large and range from 20.7% for III to 35% for II .

Five new thioantimonates have been synthesized in the presence of organic amines under solvothermal conditions and their structures determined by single-crystal X-ray diffraction. All of the compounds are layered and contain antimony-sulphide anions of stoichiometry [Sb4S7](2-), but the structure of the anion formed is dependent on the amine used in synthesis. (H3N(CH2)(4)NH3)[Sb4S7] (1) contains [Sb4S7](2-) double chains directed along [010]. Weak interchain Sb-S interactions between neighbouring chains cause the double chains to pack into layers in the ab plane. In the [001] direction, the layers of double chains alternate with doubly protonated diaminobutane molecules to which the chains are hydrogen bonded. Compounds of general formula (TH)(2)[Sb4S7] (T= CH3(CH2)(2)NH2 (2), (CH3)(2)CHNH2 (3), CH3(CH2)(3)NH2 (4) and CH3(CH2)(4)NH2 (5)) adopt a more complex structure in which [Sb3S8](7-) units are linked by Sb-3(3-) pyramids to form chains, which in turn are bridged by sulphur atoms to create sheets containing large heterorings. Pairs of such sheets form double layers of four atoms thickness that are stacked along [001]. Protonated amine molecules are located between anionic antimony-sulphide layers to which they are hydrogen bonded. Thermal analysis reveals that the decomposition temperature of materials containing [Sb4S7](2-) anions is dependent both on the structure of the anion, the lowest decomposition temperature being that of the low-dimensional phase (1) and on the identity of the amine, the decomposition temperature decreasing with an increasing number of carbon atoms and decreasing density. (c) 2005 Elsevier Inc. All rights reserved.