Synthesis and characterisation of new mixed oxides of antimony and tellurium

Abstract

Two mixed oxides of antimony and tellurium, of composition Sb₂Te₂O₉ and Sb₂TeO₇, have been synthesised by the solid-state reaction of TeO₂ and Sb₂O₃ or Sb₂O₅. Single crystals of Sb₂Te₂O₉have been obtained by transport processes. The crystallographic constants of these compounds have been determined by X-ray diffraction methods. Their i.r. absorption spectra are very similar and frequencies corresponding to the E–O–E (E = Sb or Te) vibrations have been assigned. The thermal decomposition of these oxides, at temperatures above 950 °C, leads to Sb₂O₄ as the only solid phase.