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
^ abAmador, 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.
