MATRIX-ISOLATION AND MASS-SPECTROMETRIC STUDIES ON THE VAPORIZATION OF CHROMIUM(III) BROMIDE - CHARACTERIZATION OF MOLECULAR CRBR4, CRBR3 AND CRBR2

Mass spectrometric and matrix-isolation IR studies on the vaporisation of solid chromium(III) bromide indicated the presence in the vapour o f three different chromium halide species, together with molecular bro mine. In the initial stages of heating the most volatile chromium spec ies is CrBr4, but at progressively higher temperatures molecular CrBr3 and subsequently CrBr2 are produced. The chromium and bromine isotope structure has been resolved for these latter species, and their IR sp ectra have been shown to be consistent with planar (D-3b) and linear g eometries respectively.