The room temperature conversion of nickel difluoride to hexafluoronickelate(IV) salts of alkali cations

Crystal Structures of Xenon(VI) Salts: XeF5Ni(AsF6)3, XeF5AF6 (A = Nb, Ta, Ru, Rh, Ir, Pt, Au), and XeF5A2F11 (A = Nb, Ta)

Experiments on the preparation of the new mixed cations XeF₅M(AF₆)₃ (M = Cu, Ni; A = Cr, Nb, Ta, Ru, Rh, Re, Os, Ir, Pt, Au, As), XeF₅M(SbF₆)₃ (M = Sn, Pb), and XeF₅M(BF₄)_x(SbF₆)_3-x (x = 1, 2, 3; M = Co, Mn, Ni, Zn) salts were successful only in the preparation of XeF₅Ni(AsF₆)₃. In other cases, mixtures of different products, mostly XeF₅AF₆ and XeF₅A₂F₁₁ salts, were obtained. The crystal structures of XeF₅Ni(AsF₆)₃, XeF₅TaF₆, XeF₅RhF₆, XeF₅IrF₆, XeF₅Nb₂F₁₁, XeF₅Ta₂F₁₁, and [Ni(XeF₂)₂](IrF₆)₂ were determined for the first time on single crystals at 150 K by X-ray diffraction. The crystal structures of XeF₅NbF₆, XeF₅PtF₆, XeF₅RuF₆, XeF₅AuF₆, and (Xe₂F₁₁)₂(NiF₆) were redetermined by the same method at 150 K. The crystal structure of XeF₅RhF₆ represents a new structural type in the family of XeF₅AF₆ salts, which crystallize in four different structural types. The XeF₅A₂F₁₁ salts (M = Nb, Ta) are not isotypic and both represent a new structure type. They consist of [XeF₅]⁺ cations and dimeric [A₂F₁₁]^- anions. The crystal structure of [Ni(XeF₂)₂](IrF₆)₂ is a first example of a coordination compound in which XeF₂ is coordinated to the Ni²⁺ cation.

Facile Routes to NiF(6)(2)(-), AgF(4)(-), AuF(6)(-), and PtF(6)(-) Salts Using O(2)(+) as a Source of O(2)F in Anhydrous HF

O(2)(+) salts dissolved in liquid anhydrous hydrogen fluoride (aHF) at 20 degrees C or below oxidize aHF solutions of PtF(6)(2)(-) to PtF(6)(-). The parent base of O(2)(+) salts in aHF (O(2)F((solv))) generated with alkali fluoride is long-lived below -50 degrees C. An aHF solution of O(2)F((solv)) oxidizes Au(III) to Au(V) below -50 degrees C (2O(2)F((solv)) + AuF(4)(-)((solv)) --> AuF(6)(-)((solv)) +2O(2(g))). In situ generation of O(2)F((solv)) (O(2)(+)((solv)) + F(-)((solv)) --> O(2)F((solv))) with AgF(2) or NiF(2) in suspension in the aHF made basic with alkali fluoride gives AgF(4)(-) and NiF(6)(2)(-)salts. Low solubility of AAsF(6)(A = Cs, K) in aHF provides for the metathetical preparation of (O(2))(2)PdF(6) solutions in aHF. Removal of aHF, even at -60 degrees C, results in some O(2) and F(2) loss, to a composition approaching (O(2))PdF(5).