Antimony tetroxide is an inorganic compound with the formula Sb2O4. This material, which exists as the mineral cervantite,[3] is white but reversibly yellows upon heating. The material, with empirical formula SbO2, is called antimony tetroxide to signify the presence of two kinds of Sb centers.[4]

Formation and structure

The material forms when Sb2O3 is heated in air:[5]

Sb2O3 + 0.5 O2 → Sb2O4 ΔH = −187 kJ/mol

At 800 °C, antimony(V) oxide loses oxygen to give the same material:

Sb2O5 → Sb2O4 + 0.5 O2 ΔH = −64 kJ/mol

The material is mixed valence, containing both Sb(V) and Sb(III) centers. Two polymorphs are known, one orthorhombic (shown in the infobox) and one monoclinic.[1] Both forms feature octahedral Sb(V) centers arranged in sheets with distorted Sb(III) centers bound to four oxides.

References

  1. ^ a b Amador, J.; Puebla, E. Gutierrez; Monge, M. A.; Rasines, I.; Valero, C. Ruiz (1988). "Diantimony Tetraoxides Revisited". Inorganic Chemistry. 27 (8): 1367–1370. doi:10.1021/ic00281a011.
  2. ^ a b NIOSH Pocket Guide to Chemical Hazards. "#0036". National Institute for Occupational Safety and Health (NIOSH).
  3. ^ "Cervantite". Webminerals. Retrieved 2009-06-06.
  4. ^ Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. p. 576. ISBN 978-0-08-037941-8.
  5. ^ Holleman, A. F.; Wiberg, E. "Inorganic Chemistry" Academic Press: San Diego, 2001. ISBN 0-12-352651-5.