Osmium pentafluoride is an inorganic compound with the formula OsF5. It is a blue-green solid. Like the pentafluorides of Ru, Rh, and Ir, OsF5 exists as a tetramer in the solid state.
Osmium pentafluoride can be prepared by reduction of osmium hexafluoride with iodine as a solution in iodine pentafluoride:[1]
10 OsF6 + I2 → 10 OsF5 + 2 IF5