Titanium(III) oxide

Titanium(III) oxide
Names
	IUPAC name titanium(III) oxide
	Other names titanium sesquioxide
Identifiers
CAS Number	1344-54-3 ;
3D model (JSmol)	Interactive image;
ChEBI	CHEBI:134436 ;
ChemSpider	109727;
ECHA InfoCard	100.014.271
EC Number	215-697-9;
PubChem CID	123111;
CompTox Dashboard (EPA)	DTXSID20893931 ;
	InChI InChI=1S/3O.2Ti Key: GQUJEMVIKWQAEH-UHFFFAOYSA-N;
	SMILES O=[Ti]O[Ti]=O;
Properties
Chemical formula	Ti2O3
Molar mass	143.76 g/mol
Appearance	violet black powder
Odor	odorless
Density	4.49 g/cm3
Melting point	2,130 °C (3,870 °F; 2,400 K) (decomposes)
Solubility in water	insoluble
Magnetic susceptibility (χ)	+125.6·10−6 cm3/mol
Structure
Crystal structure	Corundum
Space group	R3c (No. 167)
Lattice constant	a = 543 pm α = 56.75°, β = 90°, γ = 90°
Hazards
	GHS labelling:
Pictograms
Signal word	Warning
Hazard statements	H413
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). verify (what is ?) Infobox references

Titanium(III) oxide is the inorganic compound with the formula Ti₂ O₃. A black semiconducting solid, it is prepared by reducing titanium dioxide 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 in the form of tistarite.

Other titanium(III) oxides include LiTi₂O₄ and LiTiO₂.