Zwei- und dreikernige Fluorooxoanionen des Molybdäns und Wolframs. Kristallstrukturen von K2(NMe4)[MoV 2O2F9]·H2O und (NMe4)2[MoVI 2O4F6(H2O)] / Di- and Trinuclear Fluorooxoanions of Molybdenum and Tungsten. Crystal Structures of K2(NMe4)[MoV 2O2F9]·H2O and (NMe4)2[MoVI 2O4F6(H2O)

Abstract

From aqueous HF solutions the following fluorooxo complexes have been obtained: K2(NMe4)[Mo2O2F9]·H2O (1), K(NMe4)2[Mo3O6F9] (2), (NMe4)2[Mo2O4F6(H2O)] (3), (NMe4)2[W2O4F6(H2O)] (4) and (NEt4)2[Mo2O4F6] (5). The structures of 1 and 3 have been fully determined: Crystal data, 1, orthorhombic, space group Abm 2, a = 632.4(2), b = 2078.8(6), c = 1252.3(4) pm, Z = 4; 949 reflections, R = 0.0203. 3, orthorhombic, space group Pca 21, a = 1086.1(2), b = 1386.1(2), c = 1194.4(2) pm, Z = 4; 1826 reflections, R = 0.0231. 1 and 3 contain dimeric fluoro-bridged anions. The central atoms of 3 (and of the isostructural 4) are unequally coordinated. The anion of 2 is a cyclic fluoro-bridged trimer with cis-dioxo groups in the molecular plane. In the anion of 5 two octahedra share an edge, occupied by fluoro ligands.