Titanium(III) oxide is the

inorganic compound In chemistry, an inorganic compound is typically a chemical compound that lacks carbon–hydrogen bonds, that is, a compound that is not an organic compound. The study of inorganic compounds is a subfield of chemistry known as '' inorganic chemist ...

with the formula Ti₂ O₃. A black semiconducting solid, it is prepared by reducing

titanium dioxide Titanium dioxide, also known as titanium(IV) oxide or titania , is the inorganic compound with the chemical formula . When used as a pigment, it is called titanium white, Pigment White 6 (PW6), or CI 77891. It is a white solid that is insolubl ...

with titanium metal at 1600 °C. Ti₂O₃ adopts the Al₂O₃ (corundum) structure. It is reactive with oxidising agents. At around 200 °C there is a transition from semiconducting to metallic conducting. Titanium(III) oxide occurs naturally as the extremely rare mineral

tistarite Tistarite is an exceedingly rare mineral with the formula Ti2O3, thus being the natural analogue of titanium(III) oxide.Mindat, Tistarite, http://www.mindat.org/min-38695.html In terms of chemistry it is the titanium-analogue of hematite, corundum ...

. Other titanium(III) oxides include LiTi₂O₄ and LiTiO₂.

References

Titanium(III) compounds Sesquioxides Transition metal oxides Semiconductor materials {{inorganic-compound-stub