On the Incorporation of Transition Metal Atoms into Thiostannates: Synthesis, Crystal Structures and Spectroscopic Properties of [Ni(en)₃]₂Sn₂S₆, [Ni(dap)₃]₂Sn₂S₆ · 2 H₂O, [Co(tren)]₂Sn₂S₆, and [Ni(tren)]₂Sn₂S₆

Abstract

Abstract The four new thiostannates [Ni(en) 3 ] 2 Sn 2 S 6 ( 1 ) (en = ethylenediamine), [Ni(dap) 3 ] 2 Sn 2 S 6 · 2 H 2 O ( 2 ) (dap = 1, 2‐diaminopropane), [Co(tren)] 2 Sn 2 S 6 ( 3 ) and [Ni(tren)] 2 Sn 2 S 6 ( 4 ) (tren = tris(2‐aminoethyl)amine) were prepared under solvothermal conditions. In all compounds [Sn 2 S 6 ] 4— anions are observed as the common structural motif. This anion is composed of two SnS 4 tetrahedra sharing a common edge. In compounds 1 and 2 the transition metal cations are coordinated each by three amine ligands and therefore solvent separated complex cations as well as discrete [Sn 2 S 6 ] 4— anions are found. In compounds 3 and 4 the coordination around the transition metal ions cannot be completed by the organic ligands and the [Sn 2 S 6 ] 4— anions are connected to the transition metal cations via terminal S atoms. In both compounds the [Sn 2 S 6 ] 4— anion acts as a bidentate ligand connecting two transition metal cations by terminal S atoms. The Co 2+ cations in compound 3 are in a fivefold environment of one tetradentate tren ligand and one S atom forming discrete[Co(tren)] 2 Sn 2 S 6 units. In compound 4 the Ni 2+ ions are in a sixfold environment of one tetradentate tren ligand and two S atoms of two symmetry related [Sn 2 S 6 ] 4— anions. This connection mode leads to formation of “zig‐zag‐like” Ni—Sn 2 S 6 chains which are directed along the crystallographic c‐axis. The spectroscopic properties of compounds 1 to 3 were investigated using Raman spectroscopy. Differences in the spectra of 1 and 2 compared to 3 are observed which are caused by the covalent bonding between the Co 2+ ions and the Sn 2 S 6 4— anions in 3 .