Solvothermal Synthesis and Crystal Structure of the Non‐Centrosymmetric Thioantimonate [Ni(tren) 2 ] 2 [Ni(tren)(en)] 2 (Sb 4 S 8 ) 2 ·0.25H 2 O

The new thioantimonate [Ni(tren) 2 ] 2 [Ni(tren)(en)] 2 (Sb 4 S 8 ) 2 ·0.25H 2 O (tren = tris(2‐aminoethyl)amine; en = ethylenediamine) was obtained under solvothermal conditions. The compound crystallizes in the non‐centrosymmetric space group P 1 with a = 9.424(2), b = 13.010(3), c = 18.883(4) Å, α = 102.46(3), β = 96.11(3), γ = 90.92(3), V = 2246.1(8) Å 3 , Z = 1. Two of the unique Ni 2+ cations are octahedrally surrounded by two tridentate acting tren ligands (type 1) and the other two Ni 2+ cations are in an octahedral environment of one tetradentate tren molecule and one bidentate en ligand (type 2). The antimony atoms are in a trigonal pyramidal environment of three sulfur atoms. The SbS 3 pyramids are corner‐linked to form two individual [Sb 4 S 8 ] 4– chains running parallel to [010]. Along [001] the two different types of Ni 2+ ‐centered complex cations and the thioantimonate chains alternate. The interchain separations between [Sb 4 S 8 ] 4– chains depend on the space requirements of the two different types of complex cations. Extended N–H···S hydrogen bonding interactions between the complex cations and the anionic chains generates a three‐dimensional network.