Matrix-isolation studies on the vaporisation of alkali-metal tellurites: the characterisation of molecular M2TeO3 species (M = K, Rb or Cs)

Abstract

Solid samples of alkali-metal tellurites (M ₂ TeO ₃ ; M = K, Rb or Cs) have been heated in vacuo and the vaporisation products studied by mass spectrometry and matrix-isolation infrared spectroscopy. The molecular species M ₂ TeO ₃ are identified by mass spectrometry as important products of vaporisation, and subsequent matrix-isolation studies, which incorporated oxygen-18 data, established both vibrational assignments and probable structures for these species. In particular, molecular K ₂ TeO ₃ in argon has prominent IR absorptions at ca. 752, 742, 672, 360 and 306 cm ^-1 and a structure based on a pyramidal TeO ₃ unit.