No pyroanions: The representatives of the lanthanoid(III) fluoride oxidodimolybdates(VI) Ln FMo 2 O 7 with the Smaller Cations ( Ln = Eu – Yb)

Press to Success: Gd5FW3O16—The First Gadolinium(III) Fluoride Oxidotungstate(VI)

“…Ba 2 [WO 3 F 2 ]F 2 [10,11] and Pb 5 W 3 O 9 F 10 [12] (≡ Pb 10 [WO 3 F 3 ] 4 (W 2 O 6 F 4 )F 4 with units in parentheses being condensed and those in brackets being isolated) exhibit fluoride anions that are both bonded to W 6+ and not. Although fluoride-containing rare-earth metal oxidomolybdates with the compositions REF [ MoO 4 ] (RE = Y [13], Ce-Nd [14], Sm-Tm [15], and REFMo 2 O 7 (RE = Y [16], Eu-Yb [17]) are well known, the syntheses of the isotypic tungstates is still very challenging. In case of the aforementioned REF[ MoO 4 ] representatives, it is possible to utilize molybdenum trioxide both as reactant and as fluxing agent due to its low melting point of 802 • C [18], while in the respective reaction mixture for the tungstates, all components show a melting point above 1200 • C (e.g., GdF 3 : m.p.…”