The Simultaneous Oxidation of Tellurium and Transition Metals by AsF 5 – Syntheses and Crystal Structures of [M(SO 2 ) 6 ](Te 6 )[AsF 6 ] 6 (M = Ni, Zn) and [Cd(SO 2 ) 2 ][AsF 6 ] 2

The reactions of elemental nickel and tellurium and of ZnTe with excess AsF 5 in liquid SO 2 yield [M(SO 2 ) 6 ](Te 6 )[AsF 6 ] 6 (M = Ni, Zn) as orange crystals. The crystal structure determinations (triclinic, $P{\bar 1}$ , M = Ni: a = 1632.59(2), b = 1795.06(1), c = 1822.97(2) pm, α = 119.11(4), β = 90.78(4), γ = 106.28(4)°, V = 4408.24(8)·10 6 pm 3 , Z = 4) show the two compounds to be isotypic. The structures are made up of discrete [M(SO 2 ) 6 ] 2+ complexes, Te 6 4+ clusters and octahedral [AsF 6 ] − ions. In the [M(SO 2 ) 6 ] 2+ complexes the metal ions are surrounded octahedrally by six SO 2 molecules bound via the O atoms. The Te 6 4+ polycations are of trigonal prismatic shape with short Te–Te bonds within the triangular faces (270 pm) and long Te–Te bonds along the edges parallel to the pseudo C 3 axes of the prisms (312 pm). The arrangement of the ions is related to the Li 3 Bi structure type. [M(SO 2 ) 6 ] 2+ complexes and Te 6 4+ polycations together form a distorted cubic closest packing with all tetrahedral and octahedral interstices filled by [AsF 6 ] − ions. The analogous reaction starting from CdTe did not yield a compound containing simultaneously [Cd(SO 2 ) n ] 2+ complexes and tellurium polycations but instead Te 6 [AsF 6 ] 4 · 2 SO 2 besides [Cd(SO 2 ) 2 ][AsF 6 ] 2 were obtained. It crystallizes isotypically to [Mn(SO 2 ) 2 ][AsF 6 ] 2 (Mews, Zemva, 2001) (orthorhombic, Fdd 2, a = 1534.96(3), b = 1812.89(3), c = 892.28(3) pm, V = 2483·10 6 pm 3 , Z = 4).