Phase and conductivity studies on the systems MIIX2–MVIO3(MII= Sn or Pb; MVI= Mo or W; X = Cl or Br)

Abstract

The molten systems M^IIX₂–M^VIO₃(M^II= Sn or Pb; M^VI= Mo or W; X = Cl or Br) appear to be homogeneous liquids with up to 40 mol% of M^VIO₃. These liquids are shown by phase studies and the X-ray diffraction data of the cooled melts to be sols. The frozen products are intensely coloured and show semiconducting properties with evidence for two conduction mechanisms. The Mössbauer spectroscopic data for Sn-containing systems show that there is an increasing loss of electron density at the Sn atoms with increasing oxide content. This work provides further evidence for the ability of ns² species such as Sn^II to transfer some of their non-bonding electron pair density to either solid-state or cluster bands.