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Vanadium(III) fluoride

Names
Other names Vanadium fluoride, Vanadium trifluoride
Identifiers
CAS Number	10049-12-4
3D model (JSmol)	Interactive image
ChemSpider	16057827
ECHA InfoCard	100.030.141
PubChem CID	66230
UNII	O3S3Z32R8P
CompTox Dashboard (EPA)	DTXSID50894890
InChI InChI=1S/3FH.V/h3*1H;/q;;;+3/p-3Key: PASVSMBJEYQYSN-UHFFFAOYSA-K InChI=1/3FH.V/h3*1H;/q;;;+3/p-3Key: PASVSMBJEYQYSN-DFZHHIFOAM
SMILES ...
Properties
Chemical formula	F3V
Molar mass	107.9367 g·mol
Appearance	Yellow-green powder (anhydrous) Green powder (trihydrate)
Density	3.363 g/cm
Melting point	1,395 °C (2,543 °F; 1,668 K) at 760 mmHg (anhydrous) ~ 100 °C (212 °F; 373 K) at 760 mmHg (trihydrate) decomposes
Boiling point	Sublimes
Solubility in water	Insoluble
Solubility	Insoluble in EtOH
Magnetic susceptibility (χ)	2.757·10 cm/mol
Structure
Crystal structure	Rhombohedral, hR24
Space group	R3c, No. 167
Point group	3 2/m
Lattice constant	a = 5.17 Å, c = 13.402 Åα = 90°, β = 90°, γ = 120°
Hazards
GHS labelling:
Pictograms
Signal word	Danger
Hazard statements	H301, H311, H314, H331
Precautionary statements	P261, P280, P301+P310, P305+P351+P338, P310
NFPA 704 (fire diamond)	3 0 2
Related compounds
Other anions	Vanadium(III) chloride Vanadium(III) oxide Vanadium(III) nitride
Other cations	Vanadium(IV) fluoride
Except where otherwise noted, data are given for materials in their standard state (at 25 °C , 100 kPa). N verify (what is  ?) Infobox references

Vanadium(III) fluoride is the chemical compound with the formula VF₃. This yellow-green, refractory solid is obtained in a two-step procedure from V₂O₃. Similar to other transition-metal fluorides (such as MnF₂), it exhibits magnetic ordering at low temperatures (e.g. V₂F₆.4H₂O orders below 12 K).

Preparation

The first step entails conversion to the hexafluorovanadate(III) salt using ammonium bifluoride:

V₂O₃ + 6 (NH₄)HF₂ → 2 (NH₄)₃VF₆ + 3 H₂O

In the second step, the hexafluorovanadate is thermally decomposed.

(NH₄)₃VF₆ → 3 NH₃ + 3 HF + VF₃

The thermal decomposition of ammonium salts is a relatively common method for the preparation of inorganic solids.

VF₃ can also be prepared by treatment of V₂O₃ with HF. VF₃ is a crystalline solid with 6 coordinate vanadium atoms with bridging fluorine atoms. The magnetic moment indicates the presence of two unpaired electrons.

References

1. ^ Lide, David R., ed. (2009). CRC Handbook of Chemistry and Physics (90th ed.). Boca Raton, Florida: CRC Press. ISBN 978-1-4200-9084-0.
2. ^ Douglas, Bodie E.; Ho, Shih-Ming (2007). Structure and Chemistry of Crystalline Solids. New York: Springer Science+Business Media, Inc. p. 102. ISBN 978-0-387-26147-8.
3. ^ Sigma-Aldrich Co., Vanadium(III) fluoride. Retrieved on 2014-06-25.
4. Sturm, B. J.; Sheridan, C. W. "Vanadium(III) Fluoride" Inorganic Syntheses 1963; Vol. 7, pages 52-54. ISBN 0-88275-165-4.
5. S. Nakhal et al., Z. Kristallogr. 228, 347 (2013).doi:10.1524/zkri.2013.1664

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

• Fluorides
• Metal halides
• Vanadium(III) compounds