New Three-Dimensional Thiostannates Composed of Linked Cu₈S₁₂ Clusters and the First Example of a Mixed-Metal Cu₇SnS₁₂ Cluster

Three new compounds (enH)6+nCu40Sn15S60 (1), (enH)3Cu7Sn4S12 (2), and (trenH3)Cu7Sn4S12 (tren = tris(2-aminoethyl)amine) (3) containing Cu8S12 and Cu7SnS12 clusters have been prepared from direct solvothermal reaction of the elements in amine solvents. In 1, the cubic close-packed arrangement of Cu8S12 clusters, interconnected by capping SnS4 tetrahedra and CuS3 triangles, form two interpenetrating channel networks that are presumably filled with disordered solvent molecules. Structures 2 and 3 contain well-ordered, protonated amine molecules and Cu7SnS12 clusters. The clusters are connected by SnS4 tetrahedra to form a three-dimensional structure with ReO3 topology. 119Sn Mössbauer measurement is consistent with SnIV atoms linking, and SnII atoms within, the mixed-metal Cu7SnS12 clusters.