Vanadium(III) Fluoride

Vanadium(III) fluoride is the chemical compound with the formula VF₃. This gray-green, refractory solid is obtained in a two-step procedure from V₂O₃. 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.