Infrared and Raman spectra of some group IV complex hexafluorometallates

Abstract

The i.r. spectra (1600–40 cm.^–1), Raman spectra, and vibrational assignments are reported for some group IV complex hexafluorometallates of the type A₂MF₆(M = Ti, Zr, and Hf; A = NH₄, K, Rb, Cs, and Tl). For these complex fluorides the number of observed i.r. bands was found to be in good agreement with that calculated by use of factor-group analysis. Bands below 130 cm.^–1 in the i.r. spectra have been assigned to translatory lattice modes and the approximate frequency of the Raman-active ν₂ mode for an MF₆^2– octahedron was calculated by use of combination bands. Splitting of the Raman-active ν₅ band has also been observed in some cases.