Vanadium Pentafluoride, VF₅

Vanadium Pentafluoride, vanadic fluoride, VF₅, is of interest as the only pentahalide of vanadium. It cannot be prepared by the action of hydrofluoric acid on vanadium pentoxide, V₂O₅, or on sodium meta-vanadate, NaVO₃, because of its very strong tendency to undergo hydrolysis, with the formation of oxyfluorides. It is obtained as a white sublimate when the tetrafluoride is heated in a current of nitrogen in a platinum tube, the temperature gradually being raised from 300° to 650° C. It attacks glass and decomposes in moist air; it is therefore kept in air-tight platinum tubes. It is soluble in the common organic solvents. Density at 19° C., 2.1766. It boils at 111.2° C. under 758 mm. pressure.