Vanadium(III) oxide

Vanadium(III) oxide
Names
	Other names Vanadium sesquioxide, Vanadic oxide
Identifiers
CAS Number	1314-34-7 ;
3D model (JSmol)	Interactive image;
ECHA InfoCard	100.013.847
PubChem CID	518710;
RTECS number	YW3050000;
UNII	Y469L16CWH ;
CompTox Dashboard (EPA)	DTXSID90892259 ;
	SMILES [O-2].[V+3].[O-2].[V+3].[O-2];
Properties
Chemical formula	V2O3
Molar mass	149.881 g/mol
Appearance	Black powder
Density	4.87 g/cm3
Melting point	1,940 °C (3,520 °F; 2,210 K)
Solubility in other solvents	Insoluble
Magnetic susceptibility (χ)	+1976.0·10−6 cm3/mol
Structure
Crystal structure	Trigonal (karelianite), hR30
Space group	R-3c h, No. 167
Thermochemistry
Std molar; entropy (So298)	98.07 J/mol·K
Std enthalpy of; formation (ΔfH⦵298)	-1218.800 kJ/mol
Gibbs free energy (ΔfG˚)	-1139.052 kJ/mol
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Vanadium(III) oxide is the inorganic compound with the formula V₂O₃. It is a black solid prepared by reduction of V₂O₅ with hydrogen or carbon monoxide.^[2]^[3] It is a basic oxide dissolving in acids to give solutions of vanadium (III) complexes.^[3] V₂O₃ has the corundum structure.^[3] It is antiferromagnetic with a critical temperature of 160 K. ^[4] At this temperature there is an abrupt change in conductivity from metallic to insulating.^[4]

Upon exposure to air it gradually converts into indigo-blue V₂O₄.^[4]

In nature it occurs as the rare mineral karelianite.^[5]

References

^ ^a ^b ^c R. Robie, B. Hemingway, and J. Fisher, “Thermodynamic Properties of Minerals and Related Substances at 298.15K and 1bar Pressure and at Higher Temperatures,” US Geol. Surv., vol. 1452, 1978.[1]
^ Handbook of Preparative Inorganic Chemistry, 2nd Ed. Edited by G. Brauer, Academic Press, 1963, NY. Vol. 1. p. 1267.
^ ^a ^b ^c Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. ISBN 978-0-08-037941-8.
^ ^a ^b ^c E.M. Page, S.A.Wass (1994),Vanadium:Inorganic and Coordination chemistry, Encyclopedia of Inorganic Chemistry, John Wiley & Sons, ISBN 0-471-93620-0
^ http://www.mindat.org/min-2158.html

[usgs-1] R. Robie, B. Hemingway, and J. Fisher, “Thermodynamic Properties of Minerals and Related Substances at 298.15K and 1bar Pressure and at Higher Temperatures,” US Geol. Surv., vol. 1452, 1978.[1]

[2] Handbook of Preparative Inorganic Chemistry, 2nd Ed. Edited by G. Brauer, Academic Press, 1963, NY. Vol. 1. p. 1267.

[Greenwood-3] Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. ISBN 978-0-08-037941-8.

[Page-4] E.M. Page, S.A.Wass (1994),Vanadium:Inorganic and Coordination chemistry, Encyclopedia of Inorganic Chemistry, John Wiley & Sons, ISBN 0-471-93620-0

[5] ttp://www.mindat.org/min-2158.html

[1]

[2]

[3]

[4]

[5]

Names

Other names Vanadium sesquioxide, Vanadic oxide
Identifiers
CAS Number	1314-34-7
3D model (JSmol)	Interactive image
ECHA InfoCard	100.013.847
PubChem CID	518710
RTECS number	YW3050000
UNII	Y469L16CWH
CompTox Dashboard (EPA)	DTXSID90892259
SMILES [O-2].[V+3].[O-2].[V+3].[O-2]
Properties
Chemical formula	V₂O₃
Molar mass	149.881 g/mol
Appearance	Black powder
Density	4.87 g/cm³
Melting point	1,940 °C (3,520 °F; 2,210 K)
Solubility in other solvents	Insoluble
Magnetic susceptibility (χ)	+1976.0·10⁻⁶ cm³/mol
Structure
Crystal structure	Trigonal (karelianite), hR30
Space group	R-3c h, No. 167
Thermochemistry
Std molar entropy (S^o₂₉₈)	98.07 J/mol·K ^[1]
Std enthalpy of formation (Δ_fH^⦵₂₉₈)	-1218.800 kJ/mol ^[1]
Gibbs free energy (Δ_fG˚)	-1139.052 kJ/mol ^[1]
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).