Neptunium(V) fluoride

Neptunium(V) fluoride or neptunium pentafluoride is a chemical compound of neptunium and fluorine with the formula NpF5.

Synthesis
Neptunium(V) fluoride can be prepared by reacting neptunium(VI) fluoride with iodine:


 * $$\mathrm{10\ NpF_6\ +\ I_2\ \longrightarrow \ 10\ NpF_5\ +\ 2\ IF_5}$$

From the equation above, iodine pentafluoride is a byproduct.

Properties
Neptunium(V) fluoride thermally decomposes at 318 °C to produce neptunium(IV) fluoride and neptunium(VI) fluoride. Contrary to uranium(V) fluoride, neptunium(V) fluoride does not react with boron trichloride, but it reacts with lithium fluoride in anhydrous HF to produce LiNpF6.