Tris(piperazine-1,4-diium) bis[hexachloridoindate(III)] tetrahydrate

Abstract

The asymmetric unit of the title compound, (C4H12N2)3[InCl6]2·4H2O, consists of one and half independent piperazinium cations, an hexa­chloridoindate anion and two mol­ecules of water. The InIII ion is six-coordinated and forms a quasi-regular octa­hedral arrangement. In the crystal, alternating layers of cations and anions are arranged parallel to (10) and are linked with the water mol­ecules via intra- and inter­molecular N—H⋯O, O—H⋯Cl, C—H⋯O and N—H⋯Cl hydrogen bonds, forming a complex three-dimensional network. Additional stabilization within the layers is provided by weak inter­molecular C—H⋯Cl inter­actions.

Accessing One-Dimensional Chains of Halogenoindates(III) in Organic–Inorganic Hybrids

“…Despite the materials being isomorphous, trans -[InCl 5 ] ∞ and trans -[InBr 5 ] ∞ chains differ in the octahedral deformation arising from the corner-sharing assembly. In the case of (2Sprm) 2 InCl 5 , the axial In–Cl1 bond becomes significantly elongated (2.6550(10) Å) relative to the equatorial In–Cl distances (2.4481(8) to 2.4900(6) Å), a tendency also observed in isolated InCl 6 3– units where the elongation is caused by strong intermolecular interactions …”

“…In the case of (2Sprm) 2 InCl 5 , the axial In−Cl1 bond becomes significantly elongated (2.6550(10) Å) relative to the equatorial In−Cl distances (2.4481(8) to 2.4900(6) Å), a tendency also observed in isolated InCl 6 3− units where the elongation is caused by strong intermolecular interactions. 22 Instead, the deformation is located around the center of the octahedron, where In 3+ is displaced (∼0.270 Å) along the chain's direction from the special position, leading to a disorder of the metal ion between two positions with 0.5 occupancy each and causing a significant deviation of Br−In−Br angles from the regular 180 and 90°(Table S2).…”