Platinum hexafluoride is the chemical compound with the formulaPtF6. It is a dark-red volatile solid that forms a red gas. The compound is a unique example of platinum in the +6 oxidation state. With only four d-electrons, it is paramagnetic with a triplet ground state. PtF6 is a strong oxidant and a strong fluorinating agent. PtF6 is octahedral in both the solid state and in the gaseous state. The Pt-F bond lengths are 185 picometers.
Platinum hexafluoride can gain an electron to form the hexafluoroplatinate anion, PtF−
6. It is formed by reacting platinum hexafluoride with relatively uncationisable elements and compounds, for example with xenon to form "XePtF
6" (actually a mixture of XeFPtF
11, and Xe
6), known as xenon hexafluoroplatinate. The discovery of this reaction in 1962 proved that noble gases form chemical compounds. Previous to the experiment with xenon, PtF
6 had been shown to react with oxygen to form [O2]+[PtF6]−, dioxygenyl hexafluoroplatinate.