Vanadium(III) fluoride is the chemical compound with the formula VF3. It is a yellow-green crystalline solid with hexacoordinate vanadium atoms and bridging fluorine atoms. The magnetic moment indicates the presence of two unpaired electrons. Similar to other transition-metal fluorides (such as MnF2), it exhibits magnetic ordering at low temperatures (e.g. V2F6.4H2O orders below 12 KS. Nakhal et al., Z. Kristallogr. 228, 347 (2013).).
Preparation Vanadium(III) fluoride is obtained in a two-step procedure from V2O3.Sturm, B. J.; Sheridan, C. W. "Vanadium(III) Fluoride" Inorganic Syntheses 1963; Vol. 7, pages 52-54. .
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.
It can also be prepared by treatment of V2O3 with HF.
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