A One-Dimensional Polymeric Form of the Polycation Te82+ in the Structure of Te8[Bi4Cl14]

Z. Naturforsch. 56 b, 453^457 (2001); received March 9, 2001 catena-Octatellurium(2+), Main Group Element Clusters, Chalcogen Polycations The reaction of Te, TeCl4 and BiC^ in a sealed evacuated glass ampoule in a temperature gradient 160 to 90 °C yields Te8[Bi4Cli4] as black platelike crystals with a golden lustre which are deposited in the temperature zone 150 to 130 °C. The best yield is obtained with a Te/TeCU/BiCls molar ratio of 15/3/4. The crystal structure determination (orthorhombic, P 2i2 ,2 i, a = 879.9(3), b = 1642.3(4), c = 2267.3(8) pm, Z = 4) shows that Te8[Bi4Cl14] consists of a novel one-dimensional (Te82+)„ polycation and a two-dimensional chlorobismutate anion Bi4Cli42_. The structure of the cation consists of boat shaped Te6 rings which are connected in the 1,4-positions by Te2 groups to a one-dimensional polymeric strand. The structure is substantially different from the previously reported Teg2+ polycations in TegtWCUh and TegtMClö] (M = Zr, Hf, Re) where discrete bicyclic clusters with only weak interionic interactions are present. The Bi4Cli42_ ion can be described as built up of BiCb molecules which are connected by Cl~ ions to a two-dimensional network [(BiCl3)4(Cl)2]„.