Far-infrared spectra (20–450 cm.–1) of some halide cluster compounds of niobium and tantalum
Abstract
The far-infrared spectra of M6X14(M = Nb or Ta; X = Cl or Br) compounds have been recorded as anhydrous solids, hydrates, and pyridine adducts and in solution. The spectra all contain four strong bands and the positions and intensities of these absorptions are characteristic of M6X122+ ions. The complexity of the spectra increases in the series M6X14in solution < M6X14,8H2O < M6X14(anhydrous), and these results are interpreted in terms of deviations from the octahedral structure of an isolated M6X122+ cluster unit.