Über „Gemischt-Koordinierte”︁ einkernige Anionen. 2. Ein Oxoruthenat(VI) neuen Typs: CsK5Ru2O9 = CsK5[RuO5][RuO4]

On ?Mixed-coordinated”? isolated Anions. 2. A New Type of Oxoruthenates(VI): CsK₅Ru₂O₉ = CsK₅RuO₅]RuO₄] By heating of intimate mixtures of the oxides KO_1.1, CsO_1.2, RuO₂; K:Cs:Ru = 2.2:1:1; Ag-tube, 750°C, 34d] dark-green single crystals of CsK₅Ru₂O₉ = CsK₅RuO₅]RuO₄] were obtained for the first time. Ru⁶⁺ shows two different polyhedra in this oxide (tetrahedron, trigonal bipyramid). Untill now Rb₆TeO₅]TeO₄] 1] next to ?Mg₄GeO₆”? 3] and the isotypic high-pressure silicate 4] was the only examples known. The structure was determined by four-circle diffractometer data Mo? Kα , 1824 from 1949 I₀(hkl), SG: Pnma, R equals; 12.6%, R_w = 4.5%], parameters see text. Guinier-Simon data gave a = 1701.6(3), b = 827.6(1), c = 905.7(1) pm, Z = 4. The Madelung Part of Lattice Energy, MAPLE, Effective Coordination Numbers, ECoN, these calculated via Mean Fictive Ionic Radii, MEFIR, were calculated and discussed.