Vanadyl Difluoride, VOF₂

Vanadyl Difluoride, VOF₂, is prepared by the action of anhydrous hydrogen fluoride on vanadyl dibromide, VOBr₂. It is a yellow substance. Density at 19° C., 3.3956. A hydrated vanadyl difluoride, VOF₂.xH₂O, is obtained as microscopic blue crystals when hypovanadic oxide, VO₂, is dissolved in excess of hydrofluoric acid and the solution concentrated slowly over sulphuric acid. The following double salts have been prepared, all of which are crystalline and fairly stable:

VOF2.2NH4F VOF2.2NH4F.H2O VOF2.3NH4F 4VOF2.7NH4F.5H2O

3VOF2.8NaF.2H2O VOF2.2KF 3VOF2.7KF VOF2.2TlF

VOF2.CoF2.7H2O VOF2.NiF2.7H2O VOF2.ZnF2.7H2O VOF2.CdF2.7H2O