Synthesis and crystal structure of (Xe2F11+)2NiF6 2-

Article abstract of DOI:10.1021/ic00314a008

(Xe₂F₁₁⁺)₂NiF₆ ^2- has been prepared by the reaction between nickel difluoride, krypton difluoride, and xenon hexafluoride in anhydrous hydrogen fluoride. (Xe₂F₁₁⁺)₂NiF₆ ^2- crystallizes in the monoclinic space group I2/a with a = 17.477 (5) ?, b = 5.384 (6) ?, c = 21.300 (8) ?, β = 102.83 (3)°, V = 1954.2 ?³, Z = 4, and d_c = 3.792 g cm^-3. A structure determination using three-dimensional Mo Kα X-ray data resulted in conventional R and R_w factors of 0.070 and 0.094, respectively, for 1355 unique reflections for which I > 3σ(I). The anion NiF₆^2- is essentially octahedral; Ni-F distances range from 1.77 (1) to 1.79 (1) ?. The Xe₂Fu⁺ ion consists of two XeF₅ groups bridged by an additional common fluorine atom. The bridge bond lengths are 2.35 (1) and 2.21 (1) ? with a bridge angle of 140.3 (6)°. (Xe₂F₁₁⁺)₂NiF₆ ^2- represents the first known crystal structure of a compound with two Xe₂F₁₁⁺ cations.