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 t2g orbitals. VO is a non-stoichiometric compound, its composition varying from VO0.8 to VO1.3.[2]
-oxide-3D-vdW.png) | |
| Names | |
|---|---|
| IUPAC name Vanadium(II) oxide | |
| Other names Vanadium oxide | |
| Identifiers | |
3D model (JSmol) | |
| ECHA InfoCard | 100.031.655 |
PubChem CID | |
CompTox Dashboard (EPA) | |
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| Properties | |
| 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 | |
| Halite (cubic), cF8 | |
| Fm3m, No. 225 | |
| 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 |
| 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). | |
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]