Carbon is stable in a fluorine atmosphere up to about 400 °C, but between 420-600 °C a reaction takes place to give substoichiometric carbon monofluoride, CF0.68 appearing dark grey. With increasing temperature and fluorine pressure stoichiometries up to CF1.12 are formed. With increasing fluorine content the colour changes from dark grey to cream white indicating the loss of the aromatic character. The fluorine atoms are located in an alternating fashion above and under the former graphene plane, which is now buckled due to formation of covalent carbon-fluorine bonds. Reaction of carbon with fluorine at even higher temperature successively destroys the graphite compound to yield a mixture of gaseous fluorocarbons such as tetrafluoromethane, CF4, and tetrafluoroethylene, C2F4.[2]
In a similar fashion in 2001 it was found that the carbon allotropefullerene, C60 reacts with fluorine gas to give fullerene fluorides with stoichiometries up to C60F48.[3]
A precursor of carbon monofluoride is the fluorine-graphite intercalation compound, also called fluorine-GIC.