Chromium hexafluoride or chromium(VI) fluoride (CrF₆) is a hypothetical chemical compound between

chromium Chromium is a chemical element with the symbol Cr and atomic number 24. It is the first element in group 6. It is a steely-grey, lustrous, hard, and brittle transition metal. Chromium metal is valued for its high corrosion resistance and hardne ...

and

fluorine Fluorine is a chemical element with the symbol F and atomic number 9. It is the lightest halogen and exists at standard conditions as a highly toxic, pale yellow diatomic gas. As the most electronegative reactive element, it is extremely reacti ...

with the

chemical formula In chemistry, a chemical formula is a way of presenting information about the chemical proportions of atoms that constitute a particular chemical compound or molecule, using chemical element symbols, numbers, and sometimes also other symbols, ...

CrF₆. It was previously thought to be an unstable yellow solid decomposing at −100 °C, but this has been shown to be a misidentification of

chromium pentafluoride Chromium pentafluoride is the inorganic compound with the chemical formula CrF5. It is a red volatile solid that melts at 34 °C. It is the highest known chromium fluoride, since the hypothetical chromium hexafluoride has not yet been synt ...

, CrF₅.

Unsuccessful attempts at synthesis

CrF₆ used to be thought to be produced by exhaustive fluorination of chromium metal at 400 °C and 20 MPa of pressure, and immediate freezing out of the reaction chamber to prevent decomposition: :Cr + 3 F₂ → CrF₆ However, it has been shown that

(CrF₅) is formed instead: :2 Cr + 5 F₂ → 2 CrF₅ and that CrF₆ has yet to be synthesized.

References

Chromium(VI) compounds Chromium–halogen compounds Metal halides Hexafluorides Hypothetical chemical compounds {{inorganic-compound-stub