Vanadium(II) oxide

Vanadium(II) oxide is the inorganic compound with the idealized formula VO. It is one of the several binary vanadium oxides. It adopts a distorted NaCl structure and contains weak V−V metal to metal bonds. VO is a semiconductor owing to delocalisation of electrons in the t_2g orbitals. VO is a non-stoichiometric compound, its composition varying from VO_0.8 to VO_1.3.^[2]

Vanadium(II) oxide

Names
IUPAC name Vanadium(II) oxide
Other names Vanadium oxide
Identifiers
CAS Number	12035-98-2 Y
3D model (JSmol)	Interactive image
ECHA InfoCard	100.031.655
PubChem CID	24411
CompTox Dashboard (EPA)	DTXSID6065189
SMILES [V+2].[O-2]
Properties
Chemical formula	VO
Molar mass	66.9409 g/mol
Appearance	grey solid with metallic lustre
Density	5.758 g/cm3
Melting point	1,789 °C (3,252 °F; 2,062 K)
Boiling point	2,627 °C (4,761 °F; 2,900 K)
Refractive index (nD)	1.5763
Structure
Crystal structure	Halite (cubic), cF8
Space group	Fm3m, No. 225
Coordination geometry	Octahedral (V2+) Octahedral (O2−)
Thermochemistry
Std molar entropy (S⦵298)	39.01 J/mol·K[1]
Std enthalpy of formation (ΔfH⦵298)	−431.790 kJ/mol[1]
Gibbs free energy (ΔfG⦵)	−404.219 kJ/mol[1]
Hazards
Flash point	Non-flammable
Related compounds
Other anions	Vanadium monosulfide Vanadium monoselenide Vanadium monotelluride
Other cations	Niobium(II) oxide Tantalum(II) oxide
Related vanadium oxides	Vanadium(III) oxide Vanadium(IV) oxide Vanadium(V) oxide
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Y verify (what is YN ?) Infobox references

Diatomic VO is one of the molecules found in the spectrum of relatively cool M-type stars.^[3] A potential use of vanadium(II) monoxide is as a molecular vapor in synthetic chemical reagents in low-temperature matrices.^[4]