What is "chlorine pentafluoride"

n. (context inorganic compound English) A gaseous hypervalent binary compound, CF₅, of chlorine and fluorine.

Chlorine pentafluoride is an interhalogen compound with formula ClF. This colourless gas is an strong oxidant that was once a candidate oxidizer for rockets. The molecule adopts a square pyramidal structure with C symmetry, as confirmed by its high resolution F NMR spectrum.