A spectroscopic investigation of complexes of tin(II) fluoride with strong Lewis acids

Abstract

SbF₅, AsF₅, and BF₃ all form 1 : 1 adducts with SnF₂, and SbF₅ also forms a 1 : 2 adduct, SnF₂,2SbF₅. Tin(II) fluoride also reacts with fluorosulphuric acid to give Sn(SO₃F)₂. On the basis of their vibrational and ¹¹⁹Sn Mössbauer spectra, the 1 : 1 adducts are formulated as salts of the fluorine-bridged (Sn–F)_nⁿ⁺ cation with the anion SbF₆^–, AsF₆^–, or BF₄^–. The spectral results show that there is appreciable covalent cation–anion interaction in Sn(SO₃F)₂ and also in SnF₂,2SbF₅ which is best regarded as Sn(SbF₆)₂. The latter compound has the highest reported ¹¹⁹Sn Mssböauer isomer shift.