Vanadium tetrafluoride

Vanadium(IV) fluoride (VF4) is an inorganic compound of vanadium and fluorine. It is paramagnetic yellow-brown solid that is very hygroscopic. Unlike the corresponding vanadium tetrachloride, the tetrafluoride is not volatile because it adopts a polymeric structure. It decomposes before melting. 
Preparation and reactions.
VF4 can be prepared by treating VCl4 with HF:
It was first prepared in this way.
It decomposes at 325 °C, undergoing disproportionation to the tri- and pentafluorides:
Structure.
 The structure of VF4 is related to that of SnF4. Each vanadium centre is octahedral, surrounded by six fluoride ligands. Four of the fluoride centers bridge to adjacent vanadium centres.