Spectroscopic studies of inorganic fluoro-complexes. Part I. The 19F nuclear magnetic resonance and vibrational spectra of hexafluorometallates of Groups IVA and IVB

The infrared, Raman, and 19F n.m.r. spectra of the hexafluoro-anions of the Group IVA and IVB elements have been measured. We conclude that the predominant species present in aqueous solutions of the ammonium salts are the octahedral AF62– ions (except where A = Pb, when no definite conclusions could be drawn). In solution, the HfF72– ion dissociates into HfF62– and F–. Fluorine exchange is much more rapid when A is Zr, Hf, or Pb than when A is Si, Ge, Sn, or Ti. The tin–fluorine coupling constants in the SnF62– ion are appreciably solvent-dependent.