Synthesis, crystal structures of [M(tepa)]2(μ2-Sn2Se6)(M = Fe and Co), showing a selenidostannate bridge for transition metal complex cations

Two new selenidostannates [M(tepa)]2(μ2-Sn2Se6) (tepa = tetraethylenepentamine, M = Fe2+ 1 and Co2+ 2) were prepared by solvothermal reaction at 157 °C. Compounds 1 and 2 are isostructural. The M2+ ion has a distorted octahedral geometry comprised of five N atoms from tepa ligands and one terminal Se atom of the image anion. As a bridging ligand, image anion connects two transition metal complex cations by trans terminal Se atoms to form neutral centrosymmetric [M(tepa)]2(μ2-Sn2Se6) moieties. Their thermal and optical properties were studied.