Osmium dioxide tetrafluoride

The only known fluorine containing compounds of octa-valent osmium are osmium trioxide difluoride, OsOgF, and its salts. Osmium dioxide tetrafluoride, OsOjFg, and osmium oxide hexafluoride, OsOFg, are unknown. 

Osmium Tetrafluoride, OsF4, is obtained by passing fluorine over osmium at 280° C., the osmium having been reduced from the dioxide at red heat and rendered thereby less reactive. The small quantities of the higher fluorides simultaneously formed are removed by heating the tube, in which fluorination has been effected, to 100° C. in an atmosphere of nitrogen under low pressure. 

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