Beiträge zur Untersuchung anorganischer nichtstöchiometrischer Verbindungen. XXXVIII. Quaternäre Nioboxidfluoride des Cadmiums und Mangans mit LiNb6O15F-Struktur

Contributions to the Investigation of Inorganic Non-stoichiometric Compounds. XXXVIII. Quaternary Niobium Oxide Fluorides of Cadmium and Manganese with LiNb₆O₁₅F structure For the first time we observed an occupation of the canals in the LiNb₆O₁₅F structure by bivalent metal ions. We obtained wellshaped crystals of M_xNb₆(O, F)₁₆ (M ? Cd, Mn) by heating mixtures of MF₂ and Nb₂O₅. Cd_xNb₆(O, F)₁₆ (Mn_xNb₆(O, F)₁₆) crystallizes in the orthorhombic space group Pmma with a = 16.686 (16.677), b = 3.951 (3.952) and c = 8.907 (8.902) Å. The structure of the cadmium compound was refined to give R = 3.33% and R_w = 2.90%. The resulting formula for the investigated crystal was Cd_0.25Nb₆O_14.5F_1.5.