Synthese und Struktur eines Caesiumoxonitridomonowolframates(VI), Cs7[WN1,5O2,5]2

Synthesis and Crystal Structure of a Cesium Oxo Nitrido Monotungstate(VI), Cs₇WN_1.5O_2.5]₂ Mixtures of tungsten powder and WO₃ react with an excess of CsNH₂ in autoclaves at 650 °C to yield hygroscopic yellow crystals of cesium oxo nitrido tungstate(VI) Cs₇WN_1.5O_2.5]₂ besides Cs₆W₂N₄O₃] 1]. After the reaction the crystals are embedded in cesium metal (from thermal decomposition of CsNH₂), which was washed out by liquid ammonia. The crystals allowed a successful X‐ray structure determination. Cs₇WN_1.5O_2.5]₂ crystallizes in the space group P2₁/c with the lattice parameters a = 6.766(1) Å, b = 11.205(3) Å, c = 22.299(4) Å, β = 91.05(1)° and Z = 4. The crystal structure is built up by isolated tetrahedra WX₄] with X = N, O, which are separeted by cesium cations.