One dimensional group 12 metal undecafluoridoditantalates

• New one dimensional mercury and cadmium undecafluoridoditantalates were prepared.
• System M(II)F2/TaF5 (M = Cd, Hg) in aHF as solvent was studied.
• Geometry of Ta2F11− anion was elucidated.

The reactions between group 12 metals and the acidic TaF5 were studied in the anhydrous HF (aHF) solvent. We were able to prepare and characterize the first compounds containing metal M2+ cations and undecafluoridodimetallate anions – M(Ta2F11)2 (M = Cd, Hg) without the additional cations, anions or ligands included in the crystal structure. They both crystallize in P-1 space group with cell parameters a = 9.1571(4) Å, b = 9.8750(3) Å, c = 10.9400(7) Å, α = 94.389(4)°, β = 113.124(5)°, γ = 101.142(3)°, V = 879.81(8) Å3, Z = 2, T = 150 K (Cd(Ta2F11)2) and a = 9.1381(5) Å, b = 9.8613(6) Å, c = 11.4470(7) Å, α = 114.086(6)°, β = 102.290(5)°, γ = 100.398(5)°, V = 877.84(11) Å3, Z = 2, T = 150 K (Hg(Ta2F11)2). Metal cations connected through two anions form chains along b axis. M(HF)2(TaF6)2.nHF (M = Cd, Hg) compounds were also prepared in the MF2/TaF5 (M = Cd, Hg) system and their crystal structures were determined.

All previously prepared undecafluoridodimetallate compounds with divalent cations contain other charged or neutral species beside the cation and undecafluoridodimetallate anion in the coordination sphere. Group 12 metal cations react with excess of tantalum pentafluoride to form 1D structure composed of metal cations linked together through bidentate bridging undecafluoridoditantalate anions.Figure optionsDownload as PowerPoint slide