Matrix Isolation Studies and DFT Calculations on Molecular Alkali Metal Bromates

DFT and MP2 calculations have been carried out on a series of molecular alkali metal bromatesMBrO3 (M = Na, K, Rb, Cs), and the results compared with matrix isolation IR studies on thevaporisation of the solid salts. For M = Na, K or Rb, no ternary molecular species were detectedin the low temperature matrix, but vaporisation of solid caesium bromate at 730 K resulted in theformation of molecular CsBrO3, which was identified as having a C3v structure involvingtridentate coordination. Additionally, the DFT and MP2 calculations provide estimates of themolecular parameters for all four MBrO3 species, and for the related MXO3 species CsClO3 andCsIO3. The proven stability of MBrO3 molecules may have a bearing on the atmosphericchemistry of bromine oxo-species.