Carbon tetrafluoride

Because of the multiple carbon–fluorine bonds, and the high electronegativity of fluorine, the carbon in tetrafluoromethane has a significant positive partial charge which strengthens and shortens the four carbon–fluorine bonds by providing additional ionic character.

Thermal decomposition or combustion of CF4 produces toxic gases (carbonyl fluoride and carbon monoxide) and in the presence of water will also yield hydrogen fluoride.

It is very stable, has an atmospheric lifetime of 50,000 years, and a high greenhouse warming potential 6,500 times that of CO2.

[11] As of 2019, the man-made gases CFC-11 and CFC-12 continue to contribute a stronger radiative forcing than PFC-14.

[12] Although structurally similar to chlorofluorocarbons (CFCs), tetrafluoromethane does not deplete the ozone layer[13] because the carbon–fluorine bond is much stronger than that between carbon and chlorine.

[14] Main industrial emissions of tetrafluoromethane besides hexafluoroethane are produced during production of aluminium using Hall-Héroult process.

[15] Due to its density, tetrafluoromethane can displace air, creating an asphyxiation hazard in inadequately ventilated areas.

NFPA 704 four-colored diamond Health 1: Exposure would cause irritation but only minor residual injury. E.g. turpentine Flammability 0: Will not burn. E.g. water Instability 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g. liquid nitrogen Special hazard SA: Simple asphyxiant gas. E.g. nitrogen, helium
Mauna Loa tetrafluoromethane (CF 4 ) timeseries.
PFC-14 measured by the Advanced Global Atmospheric Gases Experiment ( AGAGE ) in the lower atmosphere ( troposphere ) at stations around the world. Abundances are given as pollution free monthly mean mole fractions in parts-per-trillion .
Atmospheric concentration of CF 4 (PFC-14) vs. similar man-made gases (right graph). Note the log scale.